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Sample records for atomic force microscope

  1. Atomic Force Microscope

    SciTech Connect (OSTI)

    Day, R.D.; Russell, P.E.

    1988-12-01

    The Atomic Force Microscope (AFM) is a recently developed instrument that has achieved atomic resolution imaging of both conducting and non- conducting surfaces. Because the AFM is in the early stages of development, and because of the difficulty of building the instrument, it is currently in use in fewer than ten laboratories worldwide. It promises to be a valuable tool for obtaining information about engineering surfaces and aiding the .study of precision fabrication processes. This paper gives an overview of AFM technology and presents plans to build an instrument designed to look at engineering surfaces.

  2. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V. C.; Wang, Chengpu

    2006-08-22

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  3. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V.; Wang, Chengpu

    2004-11-16

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  4. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V. C. (Port Jefferson, NY); Wang, Chengpu (Upton, NY)

    2003-01-01

    An atomic force microscope utilizes a pulse release system and improved method of operation to minimize contact forces between a probe tip affixed to a flexible cantilever and a specimen being measured. The pulse release system includes a magnetic particle affixed proximate the probe tip and an electromagnetic coil. When energized, the electromagnetic coil generates a magnetic field which applies a driving force on the magnetic particle sufficient to overcome adhesive forces exhibited between the probe tip and specimen. The atomic force microscope includes two independently displaceable piezo elements operable along a Z-axis. A controller drives the first Z-axis piezo element to provide a controlled approach between the probe tip and specimen up to a point of contact between the probe tip and specimen. The controller then drives the first Z-axis piezo element to withdraw the cantilever from the specimen. The controller also activates the pulse release system which drives the probe tip away from the specimen during withdrawal. Following withdrawal, the controller adjusts the height of the second Z-axis piezo element to maintain a substantially constant approach distance between successive samples.

  5. Design and analysis of a monolithic flexure atomic force microscope

    E-Print Network [OSTI]

    Ljubicic, Dean M

    2008-01-01

    This thesis details the design, manufacture, and testing of a sub-nanometer accuracy atomic force microscope. It was made to be integrated into the Sub-Atomic Measuring Machine (SAMM) in collaboration with the University ...

  6. Modeling and control of undesirable dynamics in atomic force microscopes

    E-Print Network [OSTI]

    El Rifai, Osamah M

    2002-01-01

    The phenomenal resolution and versatility of the atomic force microscope (AFM), has made it a widely-used instrument in nanotechnology. In this thesis, a detailed model of AFM dynamics has been developed. It includes a new ...

  7. Optical system for high-speed Atomic Force Microscope

    E-Print Network [OSTI]

    Lim, Kwang Yong, S.M. Massachusetts Institute of Technology

    2010-01-01

    This thesis presents the design and development of an optical cantilever deflection sensor for a high speed Atomic Force Microscope (AFM). This optical sensing system is able to track a small cantilever while the X-Y scanner ...

  8. A new ion sensing deep atomic force microscope

    SciTech Connect (OSTI)

    Drake, Barney; Randall, Connor; Bridges, Daniel; Hansma, Paul K.

    2014-08-15

    Here we describe a new deep atomic force microscope (AFM) capable of ion sensing. A novel probe assembly incorporates a micropipette that can be used both for sensing ion currents and as the tip for AFM imaging. The key advance of this instrument over previous ion sensing AFMs is that it uses conventional micropipettes in a novel suspension system. This paper focuses on sensing the ion current passively while using force feedback for the operation of the AFM in contact mode. Two images are obtained simultaneously: (1) an AFM topography image and (2) an ion current image. As an example, two images of a MEMS device with a microchannel show peaks in the ion current as the pipette tip goes over the edges of the channel. This ion sensing AFM can also be used in other modes including tapping mode with force feedback as well as in non-contact mode by utilizing the ion current for feedback, as in scanning ion conductance microscopy. The instrument is gentle enough to be used on some biological samples such as plant leaves.

  9. High-speed force mapping on living cells with a small cantilever atomic force microscope

    SciTech Connect (OSTI)

    Braunsmann, Christoph; Seifert, Jan; Rheinlaender, Johannes; Schäffer, Tilman E., E-mail: Tilman.Schaeffer@uni-tuebingen [Institute of Applied Physics and LISA, University of Tübingen, Auf der Morgenstelle 10, 72076 Tübingen (Germany)

    2014-07-15

    The imaging speed of the wide-spread force mapping mode for quantitative mechanical measurements on soft samples in liquid with the atomic force microscope (AFM) is limited by the bandwidth of the z-scanner and viscous drag forces on the cantilever. Here, we applied high-speed, large scan-range atomic force microscopy and small cantilevers to increase the speed of force mapping by ?10?100 times. This allowed resolving dynamic processes on living mouse embryonic fibroblasts. Cytoskeleton reorganization during cell locomotion, growth of individual cytoskeleton fibers, cell blebbing, and the formation of endocytic pits in the cell membrane were observed. Increasing the force curve rate from 2 to 300 Hz increased the measured apparent Young's modulus of the cells by about 10 times, which facilitated force mapping measurements at high speed.

  10. Transplanting assembly of carbon-nanotube-tipped atomic force microscope probes

    E-Print Network [OSTI]

    Soohyung, Kim

    Carbon-nanotube (CNT)-tipped atomic force microscope (AFM) probes were assembled in a deterministic and reproducible manner by transplanting a CNT bearing polymeric carrier to a microelectromechanical systems cantilever. ...

  11. Design and control of high-speed and large-range atomic force microscope

    E-Print Network [OSTI]

    Soltani Bozchalooi, Iman, 1981-

    2015-01-01

    This thesis presents the design, control and instrumentation of a novel atomic force microscope (AFM). This AFM is capable of high-speed imaging while maintaining large out-of-plane and lateral scan ranges. The primary ...

  12. Atomic force microscope with combined FTIR-Raman spectroscopy having a micro thermal analyzer

    DOE Patents [OSTI]

    Fink, Samuel D. (Aiken, SC); Fondeur, Fernando F. (North Augusta, SC)

    2011-10-18

    An atomic force microscope is provided that includes a micro thermal analyzer with a tip. The micro thermal analyzer is configured for obtaining topographical data from a sample. A raman spectrometer is included and is configured for use in obtaining chemical data from the sample.

  13. Measuring Boltzmann's constant with a low-cost atomic force microscope: An undergraduate experiment

    E-Print Network [OSTI]

    Manalis, Scott

    to directly control it. Its pedagogical advantage is that students interact with a complete instrument system measurements, students learn to apply numerous concepts such as digital sampling, Fourier-domain analysis designed and built an inexpen- sive atomic force microscope AFM system that enables this type of hands

  14. A variable-temperature nanostencil compatible with a low-temperature scanning tunneling microscope/atomic force microscope

    SciTech Connect (OSTI)

    Steurer, Wolfram, E-mail: wst@zurich.ibm.com; Gross, Leo; Schlittler, Reto R.; Meyer, Gerhard [IBM Research-Zurich, 8803 Rüschlikon (Switzerland)] [IBM Research-Zurich, 8803 Rüschlikon (Switzerland)

    2014-02-15

    We describe a nanostencil lithography tool capable of operating at variable temperatures down to 30 K. The setup is compatible with a combined low-temperature scanning tunneling microscope/atomic force microscope located within the same ultra-high-vacuum apparatus. The lateral movement capability of the mask allows the patterning of complex structures. To demonstrate operational functionality of the tool and estimate temperature drift and blurring, we fabricated LiF and NaCl nanostructures on Cu(111) at 77 K.

  15. Selective nano-patterning of graphene using a heated atomic force microscope tip

    SciTech Connect (OSTI)

    Choi, Young-Soo; Wu, Xuan; Lee, Dong-Weon, E-mail: mems@jnu.ac.kr [MEMS and Nanotechnology Laboratory, School of Mechanical Engineering, Chonnam National University, Gwangju (Korea, Republic of)] [MEMS and Nanotechnology Laboratory, School of Mechanical Engineering, Chonnam National University, Gwangju (Korea, Republic of)

    2014-04-15

    In this study, we introduce a selective thermochemical nano-patterning method of graphene on insulating substrates. A tiny heater formed at the end of an atomic force microscope (AFM) cantilever is optimized by a finite element method. The cantilever device is fabricated using conventional micromachining processes. After preliminary tests of the cantilever device, nano-patterning experiments are conducted with various conducting and insulating samples. The results indicate that faster scanning speed and higher contact force are desirable to reduce the sizes of nano-patterns. With the experimental condition of 1 ?m/s and 24 mW, the heated AFM tip generates a graphene oxide layer of 3.6 nm height and 363 nm width, on a 300 nm thick SiO{sub 2} layer, with a tip contact force of 100 nN.

  16. Characterizing absolute piezoelectric microelectromechanical system displacement using an atomic force microscope

    SciTech Connect (OSTI)

    Evans, J., E-mail: radiant@ferrodevices.com; Chapman, S., E-mail: radiant@ferrodevices.com [Radiant Technologies, Inc., 2835C Pan American Fwy NE, Albuquerque, New Mexico 87107 (United States)

    2014-08-14

    Piezoresponse Force Microscopy (PFM) is a popular tool for the study of ferroelectric and piezoelectric materials at the nanometer level. Progress in the development of piezoelectric MEMS fabrication is highlighting the need to characterize absolute displacement at the nanometer and Ångstrom scales, something Atomic Force Microscopy (AFM) might do but PFM cannot. Absolute displacement is measured by executing a polarization measurement of the ferroelectric or piezoelectric capacitor in question while monitoring the absolute vertical position of the sample surface with a stationary AFM cantilever. Two issues dominate the execution and precision of such a measurement: (1) the small amplitude of the electrical signal from the AFM at the Ångstrom level and (2) calibration of the AFM. The authors have developed a calibration routine and test technique for mitigating the two issues, making it possible to use an atomic force microscope to measure both the movement of a capacitor surface as well as the motion of a micro-machine structure actuated by that capacitor. The theory, procedures, pitfalls, and results of using an AFM for absolute piezoelectric measurement are provided.

  17. High-speed atomic force microscope based on an astigmatic detection system

    SciTech Connect (OSTI)

    Liao, H.-S.; Chen, Y.-H.; Hwu, E.-T.; Chang, C.-S.; Hwang, I.-S., E-mail: ishwang@phys.sinica.edu.tw [Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan (China); Ding, R.-F.; Huang, H.-F.; Wang, W.-M. [Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan (China); Department of Mechanical Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Huang, K.-Y. [Department of Mechanical Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

    2014-10-15

    High-speed atomic force microscopy (HS-AFM) enables visualizing dynamic behaviors of biological molecules under physiological conditions at a temporal resolution of 1s or shorter. A small cantilever with a high resonance frequency is crucial in increasing the scan speed. However, detecting mechanical resonances of small cantilevers is technically challenging. In this study, we constructed an atomic force microscope using a digital versatile disc (DVD) pickup head to detect cantilever deflections. In addition, a flexure-guided scanner and a sinusoidal scan method were implemented. In this work, we imaged a grating sample in air by using a regular cantilever and a small cantilever with a resonance frequency of 5.5 MHz. Poor tracking was seen at the scan rate of 50 line/s when a cantilever for regular AFM imaging was used. Using a small cantilever at the scan rate of 100 line/s revealed no significant degradation in the topographic images. The results indicate that a smaller cantilever can achieve a higher scan rate and superior force sensitivity. This work shows the potential for using a DVD pickup head in future HS-AFM technology.

  18. Design of a self-aligned, wide temperature range (300 mK-300 K) atomic force microscope/magnetic force microscope with 10 nm magnetic force microscope resolution

    SciTech Connect (OSTI)

    Karc?, Özgür; Dede, Münir

    2014-10-01

    We describe the design of a wide temperature range (300 mK-300 K) atomic force microscope/magnetic force microscope with a self-aligned fibre-cantilever mechanism. An alignment chip with alignment groves and a special mechanical design are used to eliminate tedious and time consuming fibre-cantilever alignment procedure for the entire temperature range. A low noise, Michelson fibre interferometer was integrated into the system for measuring deflection of the cantilever. The spectral noise density of the system was measured to be ~12 fm/?Hz at 4.2 K at 3 mW incident optical power. Abrikosov vortices in BSCCO(2212) single crystal sample and a high density hard disk sample were imaged at 10 nm resolution to demonstrate the performance of the system.

  19. High-speed imaging upgrade for a standard sample scanning atomic force microscope using small cantilevers

    SciTech Connect (OSTI)

    Adams, Jonathan D.; Nievergelt, Adrian; Erickson, Blake W.; Yang, Chen; Dukic, Maja; Fantner, Georg E., E-mail: georg.fantner@epfl.ch [Ecole Polytechnique Fédérale de Lausanne, Lausanne (Switzerland)

    2014-09-15

    We present an atomic force microscope (AFM) head for optical beam deflection on small cantilevers. Our AFM head is designed to be small in size, easily integrated into a commercial AFM system, and has a modular architecture facilitating exchange of the optical and electronic assemblies. We present two different designs for both the optical beam deflection and the electronic readout systems, and evaluate their performance. Using small cantilevers with our AFM head on an otherwise unmodified commercial AFM system, we are able to take tapping mode images approximately 5–10 times faster compared to the same AFM system using large cantilevers. By using additional scanner turnaround resonance compensation and a controller designed for high-speed AFM imaging, we show tapping mode imaging of lipid bilayers at line scan rates of 100–500 Hz for scan areas of several micrometers in size.

  20. Fermi-level shifts in graphene transistors with dual-cut channels scraped by atomic force microscope tips

    SciTech Connect (OSTI)

    Lin, Meng-Yu [Institute of Electronics, National Taiwan University, Taipei 10617, Taiwan (China); Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Chen, Yen-Hao [Department of Photonics, National Chiao Tung University, Hsinchu 30010, Taiwan (China); Su, Chen-Fung [College of Photonics, National Chiao Tung University, Tainan 71150, Taiwan (China); Chang, Shu-Wei [Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Department of Photonics, National Chiao Tung University, Hsinchu 30010, Taiwan (China); Lee, Si-Chen [Institute of Electronics, National Taiwan University, Taipei 10617, Taiwan (China); Lin, Shih-Yen, E-mail: shihyen@gate.sinica.edu.tw [Institute of Electronics, National Taiwan University, Taipei 10617, Taiwan (China); Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Department of Photonics, National Chiao Tung University, Hsinchu 30010, Taiwan (China)

    2014-01-13

    We investigate the electronic properties of p-type graphene transistors on silicon dioxide with dual-cut channels that were scraped using atomic force microscope tips. In these devices, the current is forced to squeeze into the path between the two cuts rather than flow directly through the graphene sheet. We observe that the gate voltages with minimum current shift toward zero bias as the sizes of the dual-cut regions increase. These phenomena suggest that the Fermi levels in the dual-cut regions are shifted toward the Dirac points after the mechanical scraping process.

  1. Strong Electromechanical Coupling of an Atomic Force Microscope Cantilever to a Quantum Dot Steven D. Bennett, Lynda Cockins, Yoichi Miyahara, Peter Grutter, and Aashish A. Clerk

    E-Print Network [OSTI]

    Grütter, Peter

    Strong Electromechanical Coupling of an Atomic Force Microscope Cantilever to a Quantum Dot Steven [2]. Electromechanical systems that have attracted considerable attention recently include quantum. In this Letter we study strong coupling effects, both theoretically and experimentally, in an electromechanical

  2. Stress relaxation and creep experiments with the atomic force microscope: a unified method to calculate elastic moduli and viscosities of biomaterials (and cells)

    E-Print Network [OSTI]

    Moreno-Flores, Susana; Vivanco, Maria dM; Toca-Herrera, Jose Luis

    2010-01-01

    We show that the atomic force microscope can perform stress relaxation and creep compliance measurements on living cells. We propose a method to obtain the mechanical properties of the studied biomaterial: the relaxation time, the elastic moduli and the viscosity.

  3. Effect of cantilever geometry on the optical lever sensitivities and thermal noise method of the atomic force microscope

    SciTech Connect (OSTI)

    Sader, John E.; Lu, Jianing; Mulvaney, Paul

    2014-11-15

    Calibration of the optical lever sensitivities of atomic force microscope (AFM) cantilevers is especially important for determining the force in AFM measurements. These sensitivities depend critically on the cantilever mode used and are known to differ for static and dynamic measurements. Here, we calculate the ratio of the dynamic and static sensitivities for several common AFM cantilevers, whose shapes vary considerably, and experimentally verify these results. The dynamic-to-static optical lever sensitivity ratio is found to range from 1.09 to 1.41 for the cantilevers studied – in stark contrast to the constant value of 1.09 used widely in current calibration studies. This analysis shows that accuracy of the thermal noise method for the static spring constant is strongly dependent on cantilever geometry – neglect of these dynamic-to-static factors can induce errors exceeding 100%. We also discuss a simple experimental approach to non-invasively and simultaneously determine the dynamic and static spring constants and optical lever sensitivities of cantilevers of arbitrary shape, which is applicable to all AFM platforms that have the thermal noise method for spring constant calibration.

  4. Abstract--Automation has long been recognized as an im-portant goal in AFM (Atomic Force Microscope) nanomanipu-

    E-Print Network [OSTI]

    Southern California, University of

    Abstract--Automation has long been recognized as an im- portant goal in AFM (Atomic Force on the order of 10 nm, however, automation has re- mained an elusive goal, primarily because of the spatial multi-tip arrays) or by automating the manipulation process, thus bypassing the time-consuming and labor

  5. Accurate capacitive metrology for atomic force microscopy

    E-Print Network [OSTI]

    Mazzeo, Aaron D. (Aaron David), 1979-

    2005-01-01

    This thesis presents accurate capacitive sensing metrology designed for a prototype atomic force microscope (AFM) originally developed in the MIT Precision Motion Control Lab. The capacitive measurements use a set of ...

  6. Uncertainty in least-squares fits to the thermal noise spectra of nanomechanical resonators with applications to the atomic force microscope

    SciTech Connect (OSTI)

    Sader, John E.; Yousefi, Morteza; Friend, James R.; Melbourne Centre for Nanofabrication, Clayton, Victoria 3800

    2014-02-15

    Thermal noise spectra of nanomechanical resonators are used widely to characterize their physical properties. These spectra typically exhibit a Lorentzian response, with additional white noise due to extraneous processes. Least-squares fits of these measurements enable extraction of key parameters of the resonator, including its resonant frequency, quality factor, and stiffness. Here, we present general formulas for the uncertainties in these fit parameters due to sampling noise inherent in all thermal noise spectra. Good agreement with Monte Carlo simulation of synthetic data and measurements of an Atomic Force Microscope (AFM) cantilever is demonstrated. These formulas enable robust interpretation of thermal noise spectra measurements commonly performed in the AFM and adaptive control of fitting procedures with specified tolerances.

  7. IEEE/ASME TRANSACTIONS ON MECHATRONICS, VOL. 8, NO. 3, SEPT. 2003 1 Atomic Force Microscope Probe based Controlled

    E-Print Network [OSTI]

    Sitti, Metin

    a piezoresistive AFM probe as a 1-D force sensor and nano-manipulator. In the experiments, 500 nm radius gold-coated-sized objects [1], [2], cutting [3], nano-lithography applications, etc. Hence, it can be changed from a passive observation tool to an active manipulation tool. Beside of these applications, there is another new emerging

  8. Atomic Force Microscope (Veeco Nanoman)

    E-Print Network [OSTI]

    Subramanian, Venkat

    · Place the holder in a docking station of the cantilever installation fixture and secure the probe in the groove with the spring clip Liquid Cell Docking Station In-air Probe Holder Docking Station In-air Probe Holder #12;Loading Probe to AFM Head · Fully tighten the dovetail knob (rotate clockwise) · Lift the AFM

  9. Contact stiffness of layered materials for ultrasonic atomic force microscopy

    E-Print Network [OSTI]

    Contact stiffness of layered materials for ultrasonic atomic force microscopy G. G. Yaralioglu,a) F the contact stiffness between a layered material and an ultrasonic atomic force microscope UAFM tip of the method for modeling defects and power loss due to radiation in layered materials. © 2000 American

  10. Construction of a quantum gas microscope for fermionic atoms

    E-Print Network [OSTI]

    Ramasesh, Vinay (Vinay V.)

    2013-01-01

    This thesis reports the construction of a novel apparatus for experiments with ultracold atoms in optical lattices: the Fermi gas microscope. Improving upon similar designs for bosonic atoms, our Fermi gas microscope has ...

  11. On single-molecule DNA sequencing with atomic force microscopy using functionalized carbon nanotube probes

    E-Print Network [OSTI]

    Burns, Daniel James

    2004-01-01

    A novel DNA sequencing method is proposed based on the specific binding nature of nucleotides and measured by an atomic force microscope (AFM). A single molecule of DNA is denatured and immobilized on an atomically fiat ...

  12. Note: Artificial neural networks for the automated analysis of force map data in atomic force microscopy

    SciTech Connect (OSTI)

    Braunsmann, Christoph; Schäffer, Tilman E., E-mail: tilman.schaeffer@uni-tuebingen.de [Institute of Applied Physics and LISA, University of Tübingen, Auf der Morgenstelle 10, 72076 Tübingen (Germany)

    2014-05-15

    Force curves recorded with the atomic force microscope on structured samples often show an irregular force versus indentation behavior. An analysis of such curves using standard contact models (e.g., the Sneddon model) would generate inaccurate Young's moduli. A critical inspection of the force curve shape is therefore necessary for estimating the reliability of the generated Young's modulus. We used a trained artificial neural network to automatically recognize curves of “good” and of “bad” quality. This is especially useful for improving the analysis of force maps that consist of a large number of force curves.

  13. Friction, Adhesion, and Deformation: Dynamic Measurements with the Atomic Force Phil Attard

    E-Print Network [OSTI]

    Attard, Phil

    Friction, Adhesion, and Deformation: Dynamic Measurements with the Atomic Force Microscope Phil. Adhesion Sci. Technol. 16, 753­791 (2002).) Running title: Friction, Adhesion, and Deformation Abstract for the friction force microscope, quantitative measurements of friction and the ef- fect of adhesion, measurement

  14. Nanoscale characterization of solution-cast poly(vinylidene fluoride) thinfilms using atomic force microscopy 

    E-Print Network [OSTI]

    Jee, Tae Kwon

    2007-04-25

    This thesis research focuses on the characterization of thinfilms made of poly(vinylidene fluoride) (PVDF) using an atomic force microscope. Thinfilms of PVDF were fabricated by a spin coating method with different conditions and characterized using...

  15. Magnetic nanowire based high resolution magnetic force microscope probes

    E-Print Network [OSTI]

    Qin, Lu-Chang

    -resolution magnetic force microscope probes using preformed magnetic nanowires. Nickel and cobalt nanowires produced of either electron beam deposition and/or focused ion beam milling. Attachment/ growth of carbon nanotubes carbon nanotube MWNT capped with a magnetic catalyst particle onto the apex of a commercial Si cantilever

  16. Study of dynamic effects in microparticle adhesion using Atomic force microscopy 

    E-Print Network [OSTI]

    Kaushik, Anshul

    2005-02-17

    and Atomic force Microscope etc. Some of them are described below. 9 JKR apparatus for force measurements in contact mechanics (20): This apparatus is used to measure the adhesion force between a particle and a surface in contact. The apparatus... computer to get commands and send displacement information measured by a displacement sensor. This apparatus can be sealed in a thermal and humidity control chamber. The contact diameter between the samples is measured by a camera placed on top...

  17. Force Density Balance inside the Hydrogen Atom

    E-Print Network [OSTI]

    Himpsel, F J

    2015-01-01

    Motivated by the long-debated question about the internal stability of the electron, the force densities acting on the charge density of the 1s electron in the H atom are investigated. The problem is mapped onto the canonical formalism for a classical Dirac field coupled to the electric field of an external point charge. An explicit calculation shows that the attractive Coulomb force density is balanced exactly at every point in space by the repulsive confinement force density. The latter requires evaluating the divergence of the stress tensor for the 1s solution of the Dirac equation. Such a local force balance goes beyond the global stability criteria that are usually given for the H atom. This concept is extended to the internal stability of any charged particle by investigating the force densities acting on its surrounding vacuum polarization. At large distances one has to consider only the charge density of virtual electrons and positrons, induced by a point charge in the vacuum of quantum electrodynamic...

  18. Friction forces on atoms after acceleration

    E-Print Network [OSTI]

    Francesco Intravaia; Vanik E. Mkrtchian; Stefan Buhmann; Stefan Scheel; Diego A. R. Dalvit; Carsten Henkel

    2015-02-04

    The aim of this paper is to revisit the calculation of atom-surface quantum friction in the quantum field theory formulation put forward by Barton [New J. Phys. 12 (2010) 113045]. We show that the power dissipated into field excitations and the associated friction force depend on how the atom is boosted from being initially at rest to a configuration in which it is moving at constant velocity (v) parallel to the planar interface. In addition, we point out that there is a subtle cancellation between the one-photon and part of the two-photon dissipating power, resulting in a leading order contribution to the frictional power which goes as v^4. These results are also confirmed by an alternative calculation of the average radiation force, which scales as v^3.

  19. Design and construction of a magnetic force microscope 

    E-Print Network [OSTI]

    Khandekar, Sameer Sudhakar

    2005-08-29

    compared to the previous designs. Some of the anticipated system specifications are: 1) room temperature scanning range of 175?? 175 ??m, 2) low temperature scanning range between 35-50 ??m, 3) smallest detectable magnetic force in the range of one pN and 4...

  20. Towards a quantum gas microscope for fermionic atoms

    E-Print Network [OSTI]

    Ramasesh, Vinay (Vinay V.)

    2012-01-01

    This thesis reports the achievement of a two-species apparatus for use in an upcoming experiment with fermionic ultracold atomic gases. First, we describe the construction of a laser system capable of cooling and trapping ...

  1. Workshop on Atomic Force Microscopy, Nanometrology and More ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Swarna Addepalli 2012.12.17 One of my colleagues from our global research center in India, K.G. V. Siva Kumar (Sivakumar), recently attended a workshop on Atomic Force...

  2. Microscopic Lensing by a Dense, Cold Atomic Sample

    E-Print Network [OSTI]

    Stetson Roof; Kasie Kemp; Mark Havey; I. M. Sokolov; D. V. Kupriyanov

    2014-12-01

    We demonstrate that a cold, dense sample of 87Rb atoms can exhibit a micron-scale lensing effect, much like that associated with a macroscopically-sized lens. The experiment is carried out in the fashion of traditional z-scan measurements but in much weaker fields and where close attention is paid to the detuning dependence of the transmitted light. The results are interpreted using numerical simulations and by modeling the sample as a thin lens with a spherical focal length.

  3. Controlling Nanometer-Scale Crystal Growth on a Model Biomaterial with a Scanning Force Microscope

    E-Print Network [OSTI]

    Dickinson, J. Thomas

    Controlling Nanometer-Scale Crystal Growth on a Model Biomaterial with a Scanning Force Microscope the changes in a quantitative fashion. Single-crystal brushite, an important biomineral and biomaterial,7 (enamel, dentine, bone) and pathological (dental cavities, kidney stones) calcifications. Under weakly

  4. Using Atom Interferometry to Search for New Forces

    SciTech Connect (OSTI)

    Wacker, Jay G.; /SLAC

    2009-12-11

    Atom interferometry is a rapidly advancing field and this Letter proposes an experiment based on existing technology that can search for new short distance forces. With current technology it is possible to improve the sensitivity by up to a factor of 10{sup 2} and near-future advances will be able to rewrite the limits for forces with ranges from 100 {micro}m to 1km.

  5. Potential contributions of noncontact atomic force microscopy for the future Casimir force measurements

    E-Print Network [OSTI]

    W. J. Kim; U. D. Schwarz

    2010-10-18

    Surface electric noise, i.e., the non-uniform distribution of charges and potentials on a surface, poses a great experimental challenge in modern precision force measurements. Such a challenge is encountered in a number of different experimental circumstances. The scientists employing atomic force microscopy (AFM) have long focused their efforts to understand the surface-related noise issues via variants of AFM techniques, such as Kelvin probe force microscopy or electric force microscopy. Recently, the physicists investigating quantum vacuum fluctuation phenomena between two closely-spaced objects have also begun to collect experimental evidence indicating a presence of surface effects neglected in their previous analyses. It now appears that the two seemingly disparate science communities are encountering effects rooted in the same surface phenomena. In this report, we suggest specific experimental tasks to be performed in the near future that are crucial not only for fostering needed collaborations between the two communities, but also for providing valuable data on the surface effects in order to draw the most realistic conclusion about the actual contribution of the Casimir force (or van der Waals force) between a pair of real materials.

  6. Spin microscope based on optically detected magnetic resonance

    DOE Patents [OSTI]

    Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

    2010-06-29

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  7. Spin microscope based on optically detected magnetic resonance

    DOE Patents [OSTI]

    Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

    2009-11-10

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of impaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  8. Spin microscope based on optically detected magnetic resonance

    DOE Patents [OSTI]

    Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

    2007-12-11

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  9. Spin microscope based on optically detected magnetic resonance

    DOE Patents [OSTI]

    Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

    2009-10-27

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  10. Spin microscope based on optically detected magnetic resonance

    DOE Patents [OSTI]

    Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)

    2010-07-13

    The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.

  11. Electromagnetic model for near-field microwave microscope with atomic resolution: Determination of tunnel junction impedance

    SciTech Connect (OSTI)

    Reznik, Alexander N.

    2014-08-25

    An electrodynamic model is proposed for the tunneling microwave microscope with subnanometer space resolution as developed by Lee et al. [Appl. Phys. Lett. 97, 183111 (2010)]. Tip-sample impedance Z{sub a} was introduced and studied in the tunneling and non-tunneling regimes. At tunneling breakdown, the microwave current between probe and sample flows along two parallel channels characterized by impedances Z{sub p} and Z{sub t} that add up to form overall impedance Z{sub a}. Quantity Z{sub p} is the capacitive impedance determined by the near field of the probe and Z{sub t} is the impedance of the tunnel junction. By taking into account the distance dependences of effective tip radius r{sub 0}(z) and tunnel resistance R{sub t}(z)?=?Re[Z{sub t}(z)], we were able to explain the experimentally observed dependences of resonance frequency f{sub r}(z) and quality factor Q{sub L}(z) of the microscope. The obtained microwave resistance R{sub t}(z) and direct current tunnel resistance R{sub t}{sup dc}(z) exhibit qualitatively similar behavior, although being largely different in both magnitude and the characteristic scale of height dependence. Interpretation of the microwave images of the atomic structure of test samples proved possible by taking into account the inductive component of tunnel impedance ImZ{sub t}?=??L{sub t}. Relation ?L{sub t}/R{sub t}???0.235 was obtained.

  12. Deposition and atomic force microscopy of individual phthalocyanine polymers between nanofabricated electrodes

    E-Print Network [OSTI]

    Dekker, Cees

    Deposition and atomic force microscopy of individual phthalocyanine polymers between nanofabricated of cellulose using the Langmuir­Blodgett deposition technique. Atomic force microscopy was used to study- layer of an insulating molecule.6 We show that this method leads to a controlled deposition and strong

  13. Atomic force microscopy of nickel dot arrays with tuning fork and nanotube probe

    E-Print Network [OSTI]

    Chandrasekhar, Venkat

    Atomic force microscopy of nickel dot arrays with tuning fork and nanotube probe S. Rozhok,a) S microscopy are combined with the unique properties of carbon nanotubes to improve the spatial resolution of atomic force microscopy AFM images of nickel dot arrays. These arrays have high relief features

  14. Atomic force microscopy investigation of the giant mimivirus

    SciTech Connect (OSTI)

    Kuznetsov, Yuri G.; Xiao Chuan; Sun Siyang; Raoult, Didier; Rossmann, Michael; McPherson, Alexander

    2010-08-15

    Mimivirus was investigated by atomic force microscopy in its native state following serial degradation by lysozyme and bromelain. The 750-nm diameter virus is coated with a forest of glycosylated protein fibers of lengths about 140 nm with diameters 1.4 nm. Fibers are capped with distinctive ellipsoidal protein heads of estimated Mr = 25 kDa. The surface fibers are attached to the particle through a layer of protein covering the capsid, which is in turn composed of the major capsid protein (MCP). The latter is organized as an open network of hexagonal rings with central depressions separated by 14 nm. The virion exhibits an elaborate apparatus at a unique vertex, visible as a star shaped depression on native particles, but on defibered virions as five arms of 50 nm width and 250 nm length rising above the capsid by 20 nm. The apparatus is integrated into the capsid and not applied atop the icosahedral lattice. Prior to DNA release, the arms of the star disengage from the virion and it opens by folding back five adjacent triangular faces. A membrane sac containing the DNA emerges from the capsid in preparation for fusion with a membrane of the host cell. Also observed from disrupted virions were masses of distinctive fibers of diameter about 1 nm, and having a 7-nm periodicity. These are probably contained within the capsid along with the DNA bearing sac. The fibers were occasionally observed associated with toroidal protein clusters interpreted as processive enzymes modifying the fibers.

  15. High-speed tapping-mode atomic force microscopy using a Q-controlled regular cantilever acting as the actuator: Proof-of-principle experiments

    SciTech Connect (OSTI)

    Balantekin, M.; Sat?r, S.; Torello, D.; De?ertekin, F. L.

    2014-12-15

    We present the proof-of-principle experiments of a high-speed actuation method to be used in tapping-mode atomic force microscopes (AFM). In this method, we do not employ a piezotube actuator to move the tip or the sample as in conventional AFM systems, but, we utilize a Q-controlled eigenmode of a cantilever to perform the fast actuation. We show that the actuation speed can be increased even with a regular cantilever.

  16. Force on a neutral atom near conducting microstructures

    E-Print Network [OSTI]

    Claudia Eberlein; Robert Zietal

    2006-11-09

    We derive the non-retarded energy shift of a neutral atom for two different geometries. For an atom close to a cylindrical wire we find an integral representation for the energy shift, give asymptotic expressions, and interpolate numerically. For an atom close to a semi-infinite halfplane we determine the exact Green's function of the Laplace equation and use it derive the exact energy shift for an arbitrary position of the atom. These results can be used to estimate the energy shift of an atom close to etched microstructures that protrude from substrates.

  17. Directional spontaneous emission and lateral Casimir-Polder force on an atom close to a nanofiber

    E-Print Network [OSTI]

    Stefan Scheel; Stefan Yoshi Buhmann; Christoph Clausen; Philipp Schneeweiss

    2015-05-06

    We study the spontaneous emission of an excited atom close to an optical nanofiber and the resulting scattering forces. For a suitably chosen orientation of the atomic dipole, the spontaneous emission pattern becomes asymmetric and a resonant Casimir--Polder force parallel to the fiber axis arises. For a simple model case, we show that the such a lateral force is due to the interaction of the circularly oscillating atomic dipole moment with its image inside the material. With the Casimir--Polder energy being constant in the lateral direction, the predicted lateral force does not derive from a potential in the usual way. Our results have implications for optical force measurements on a substrate as well as for laser cooling of atoms in nanophotonic traps.

  18. arXiv:1304.3175v2[nucl-th]17Apr2013 Microscopic optical potential from chiral nuclear forces

    E-Print Network [OSTI]

    Weise, Wolfram

    -order terms from both two- and three-nucleon forces give rise to real, energy-independent contributions to the nucleon self-energy. The Hartree-Fock contribution from the two-nucleon force is attractive and stronglyarXiv:1304.3175v2[nucl-th]17Apr2013 Microscopic optical potential from chiral nuclear forces J. W

  19. Atomic Force Microscopy Studies of Lipophosphoglycan (LPG) Molecules in Lipid Bilayers

    SciTech Connect (OSTI)

    LAST, JULIE A.; HUBER, TINA; SASAKI, DARRYL Y.; SALVATORE, BRIAN; TURCO, SALVATORE J.

    2003-03-01

    Lipophosphoglycan (LPG) is a lypopolysaccharide found on the surface of the parasite Leishmania donovani that is thought to play an essential role in the infection of humans with leishamniasis. LPG acts as an adhesion point for the parasite to the gut of the sand fly, whose bite is responsible for transmitting the disease. In addition, LPG acts to inhibit protein kinase C (PKC) in the human macrophage, possibly by structural changes in the membrane. The Ca{sup 2+} ion is believed to play a role in the infection cycle, acting both as a crosslinker between LPG molecules and by playing a part in modulating PKC activity. To gain insight into the structure of LPG within a supported lipid membrane and into the structural changes that occur due to Ca{sup 2+} ions, we have employed the atomic force microscope (AFM). We have observed that the LPG molecules inhibit bilayer fusion, resulting in bilayer islands on the mica surface. One experiment suggests that the LPG molecules are parallel to the mica surface and that the structure of the LPG changes upon addition of Ca{sup 2+}, with an increase in the height of the LPG molecules from the bilayer surface and an almost complete coverage of LPG on the bilayer island.

  20. Behaviour of nanocolloidal particles on mica: investigations using atomic force microscopy 

    E-Print Network [OSTI]

    Walker, Richard John

    2010-01-01

    In this thesis we used atomic force microscopy (AFM) to investigate systematically the behaviour of both electrostatically stabilised silica and sterically stabilised polystyrene (PS) colloidal systems on freshly cleaved ...

  1. A force field for virtual atom molecular mechanics of proteins

    E-Print Network [OSTI]

    Hendrickson, Wayne A.

    , Columbia University, New York, NY 10032 Contributed by Wayne A. Hendrickson, July 13, 2009 (sent for review for which crystallography can specify atomic details of alternative end states, but the course distribution of the energy terms extracted from crystallographic data, and it is formulated to capture features

  2. Detection of Percolating Paths in PMMA/CB Segregated Network Composites Using Electrostatic Force Microscopy and Conductive Atomic Force Microscopy

    SciTech Connect (OSTI)

    Waddell, J. [Georgia Institute of Technology; Ou, R. [Georgia Institute of Technology; Gupta, S. [Georgia Institute of Technology; Parker, A. [Georgia Institute of Technology; Gerhardt, Dr. Rosario [Georgia Institute of Technology; Seal, Katyayani [ORNL; Kalinin, Sergei V [ORNL; Baddorf, Arthur P [ORNL

    2009-01-01

    Composite specimens possessing polyhedral segregated network microstructures require a very small amount of nanosize filler, <1 vol %, to reach percolation because percolation occurs by accumulation of the fillers along the edges of the deformed polymer matrix particles. In this paper, electrostatic force microscopy (EFM) and conductive atomic force microscopy (C-AFM) were used to confirm the location of the nanosize fillers and the corresponding percolating paths in polymethyl methacrylate/carbon black composites. The EFM and C-AFM images revealed that the polyhedral polymer particles were coated with filler, primarily on the edges as predicted by the geometric models provided.

  3. The World's Smallest Fountain Pen? The miniscule tip on an atomic-force microscope (AFM) helps

    E-Print Network [OSTI]

    Espinosa, Horacio D.

    , which range from pigments for creating patterns to organic materials for creating sensors, but they suffer from difficulties with maintaining a regular ink supply. The new "nanofountain probe" can paint

  4. Viscoelastic Study Using an Atomic Force Microscope Modified to Operate as a Nanorheometer

    E-Print Network [OSTI]

    Attard, Phil

    pharmaceutical compounds, through to polymer composites,blends,novelorganicsemiconductornetworks, and even,11,12 Although category I nanorheology can be conducted without any subsequent modification to the existing AFM

  5. Photo-thermal quartz tuning fork excitation for dynamic mode atomic force microscope

    SciTech Connect (OSTI)

    Bontempi, Alexia; Teyssieux, Damien; Thiery, Laurent; Hermelin, Damien; Vairac, Pascal; Friedt, Jean-Michel

    2014-10-13

    A photo-thermal excitation of a Quartz Tuning Fork (QTF) for topographic studies is introduced. The non-invasive photo-thermal excitation presents practical advantages compared to QTF mechanical and electrical excitations, including the absence of the anti-resonance and its associated phase rotation. Comparison between our theoretical model and experiments validate that the optical transduction mechanism is a photo-thermal rather than photo-thermoacoustic phenomenon. Topographic maps in the context of near-field microscopy distance control have been achieved to demonstrate the performance of the system.

  6. Fabrication of two-dimensional arrays of nanometer-size clusters with the atomic force microscope

    E-Print Network [OSTI]

    . This feature minimized contamination due to water vapor or hydrocarbon adsorption on the sub- strate surface

  7. Atomic Force Microscope Images of Nanobubbles on a Hydrophobic Surface and Corresponding

    E-Print Network [OSTI]

    Attard, Phil

    -Separation Data J. W. G. Tyrrell and P. Attard* Ian Wark Research Institute, University of South Australia, Mawson Lakes, SA 5095, Australia Received July 30, 2001. In Final Form: October 17, 2001 Domains, apparently or tapping mode imaging at high drive amplitudes. They are not present in a solvaphilic fluid (ethanol

  8. Atomic Force Microscope Based Near-field Imaging for Probing Cell Surface Interactions 

    E-Print Network [OSTI]

    Amini, Sina

    2013-03-26

    on the microsphere surface. For the EF technique, quantum dot (QD)-embedded polystyrene microspheres were used to couple light into whispering gallery modes (WGMs) inside the microspheres; the resulting EF at the surface of the microsphere was used as a near...

  9. Local detection of X-ray spectroscopies with an in-situ Atomic Force Microscope

    E-Print Network [OSTI]

    Rodrigues, Mario S; LE Denmat, Simon; Chevrier, Joel; Felici, Roberto; Comin, Fabio

    2008-01-01

    We show how the in situ combination of Scanning Probe Microscopies (SPM) with X-ray microbeams enables many new experiments in the synchrotron radiation domain. Our instrument is based on an optics free AFM/STM that can be directly installed on most of the SR X-ray end stations. The instrument can be simply used for AFM imaging of the investigated sample or it can be used for detection of photoemitted electrons with a sharp STM like tungsten tip, thus leading to locally measure the EXAFS signal. Alternatively one can measure the photons absorbed by the tip, thus locally detecting diffraction. In this paper, we show examples of both measurements. We also describe the experimental setup and the tip-beam interaction that is a key point for alignment procedures. We finally show how these features can be exploited in an extended variety of domains, nanosciences and nanomechanics, just to name a few.

  10. A test method for determining adhesion forces and Hamaker constants of cementitious materials using atomic force microscopy

    SciTech Connect (OSTI)

    Lomboy, Gilson [Department of Civil, Construction, and Environmental Engineering, Iowa State University, Ames, Iowa 50011 (United States); Sundararajan, Sriram, E-mail: srirams@iastate.edu [Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011 (United States); Wang Kejin [Department of Civil, Construction, and Environmental Engineering, Iowa State University, Ames, Iowa 50011 (United States); Subramaniam, Shankar [Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011 (United States)

    2011-11-15

    A method for determining Hamaker constant of cementitious materials is presented. The method involved sample preparation, measurement of adhesion force between the tested material and a silicon nitride probe using atomic force microscopy in dry air and in water, and calculating the Hamaker constant using appropriate contact mechanics models. The work of adhesion and Hamaker constant were computed from the pull-off forces using the Johnson-Kendall-Roberts and Derjagin-Muller-Toropov models. Reference materials with known Hamaker constants (mica, silica, calcite) and commercially available cementitious materials (Portland cement (PC), ground granulated blast furnace slag (GGBFS)) were studied. The Hamaker constants of the reference materials obtained are consistent with those published by previous researchers. The results indicate that PC has a higher Hamaker constant than GGBFS. The Hamaker constant of PC in water is close to the previously predicted value C{sub 3}S, which is attributed to short hydration time ({<=} 45 min) used in this study.

  11. Nuclear Pairing from Two-body Microscopic Forces: Analysis of the Cooper Pair Wavefunctions

    E-Print Network [OSTI]

    P. Finelli; S. Maurizio; J. W. Holt

    2014-11-27

    In a recent paper we studied the behavior of the pairing gaps $\\Delta_F$ as a function of the Fermi momentum $k_F$ for neutron and nuclear matter in all relevant angular momentum channels where superfluidity is believed to naturally emerge. The calculations employed realistic chiral nucleon-nucleon potentials with the inclusion of three-body forces and self-energy effects. In this contribution, after a detailed description of the numerical method we employed in the solution of the BCS equations, we will show a preliminary analysis of the Cooper pair wavefunctions.

  12. Bacterial Immobilization for Imaging by Atomic Force Microscopy

    SciTech Connect (OSTI)

    Allison, David P [ORNL; Sullivan, Claretta [Eastern Virginia Medical School; Mortensen, Ninell P [ORNL; Retterer, Scott T [ORNL; Doktycz, Mitchel John [ORNL

    2011-01-01

    AFM is a high-resolution (nm scale) imaging tool that mechanically probes a surface. It has the ability to image cells and biomolecules, in a liquid environment, without the need to chemically treat the sample. In order to accomplish this goal, the sample must sufficiently adhere to the mounting surface to prevent removal by forces exerted by the scanning AFM cantilever tip. In many instances, successful imaging depends on immobilization of the sample to the mounting surface. Optimally, immobilization should be minimally invasive to the sample such that metabolic processes and functional attributes are not compromised. By coating freshly cleaved mica surfaces with porcine (pig) gelatin, negatively charged bacteria can be immobilized on the surface and imaged in liquid by AFM. Immobilization of bacterial cells on gelatin-coated mica is most likely due to electrostatic interaction between the negatively charged bacteria and the positively charged gelatin. Several factors can interfere with bacterial immobilization, including chemical constituents of the liquid in which the bacteria are suspended, the incubation time of the bacteria on the gelatin coated mica, surface characteristics of the bacterial strain and the medium in which the bacteria are imaged. Overall, the use of gelatin-coated mica is found to be generally applicable for imaging microbial cells.

  13. Data acquisition system for high speed atomic force microscopy Georg E. Fantner,a

    E-Print Network [OSTI]

    Hansma, Paul

    Data acquisition system for high speed atomic force microscopy Georg E. Fantner,a Paul Hegarty higher scan speeds, the need for data acquisition systems DAQ that are capable of handling the increased amounts of data in real time arises. We have developed a low cost data acquisition and scan control system

  14. The dissipated power in atomic force microscopy due to interactions with a capillary fluid layer

    E-Print Network [OSTI]

    Paul, Mark

    The dissipated power in atomic force microscopy due to interactions with a capillary fluid layer N July 2008; published online 23 September 2008 We study the power dissipated by the tip interactions of the model are entirely conservative and the dissipated power is due to the hysteretic nature

  15. Very large-scale structures in sintered silica aerogels as evidenced by atomic force microscopy and ultra-small angle

    E-Print Network [OSTI]

    Demouchy, Sylvie

    Very large-scale structures in sintered silica aerogels as evidenced by atomic force microscopy of silica aerogels has been extensively studied mainly by scattering techniques (neutrons, X-rays, light) and atomic force microscopy (AFM) experiments have been carried out on aerogels at dierent steps of densi

  16. Interactions between collagen IX and biglycan measured by atomic force microscopy

    SciTech Connect (OSTI)

    Chen, C.-H. [Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX (United States); Department of Physical Medicine and Rehabilitation, Kaohsiung Medical University Hospital, Taiwan (China); Yeh, M.-L. [Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX (United States); Geyer, Mark [Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX (United States); Wang, Gwo-Jaw [Department of Orthopedics, Kaohsiung Medical University School of Medicine, Kaohsiung, Taiwan (China); Huang, M.-H. [Department of Physical Medicine and Rehabilitation, Kaohsiung Medical University Hospital, Taiwan (China); Heggeness, Michael H. [Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX (United States); Hoeoek, Magnus [Institute of Biosciences and Technology, Texas A and M University, Houston, TX (United States); Luo, Z.-P. [Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX (United States)]. E-mail: luo@bcm.tmc.edu

    2006-01-06

    The stability of the lattice-like type II collagen architecture of articular cartilage is paramount to its optimal function. Such stability not only depends on the rigidity of collagen fibrils themselves, but more importantly, on their interconnections. One known interconnection is through type IX and biglycan molecules. However, the mechanical properties of this interaction and its role in the overall stability remain unrevealed. Using atomic force microscopy, this study directly measured the mechanical strength (or the rupture force) of a single bond between collagen IX and biglycan. The results demonstrated that the rupture force of this single bond was 15 pN, which was significantly smaller than those of other known molecule interactions to date. This result suggested that type IX collagen and biglycan interaction may be the weak link in the cartilage collagen architecture, vulnerable to abnormal joint force and associated with disorders such as osteoarthritis.

  17. Electrostatic Force Microscopy Characterization of Trioctylphosphine Oxide Self-assembled Monolayers on Graphite

    E-Print Network [OSTI]

    orientation of SAMs. The invention of the scanning probe microscope (SPM)12,13 has provided scientists resolution by SPM. Electrostatic force microscopy (EFM),16 a variant of atomic force microscopy (AFM),13 can

  18. Topography and Mechanical Property Mapping of International Simple Glass Surfaces with Atomic Force Microscopy

    SciTech Connect (OSTI)

    Hopf, Juliane [ORNL; Pierce, Eric M [ORNL

    2014-01-01

    Quantitative Nanomechanical Peak Force (PF-QNM) TappingModeTM atomic force microscopy measurements are presented for the first time on polished glass surfaces. The PF-QNM technique allows for topography and mechanical property information to be measured simultaneously at each pixel. Results for the international simple glass which represents a simplified version of SON68 glass suggests an average Young s modulus of 78.8 15.1 GPa is within the experimental error of the modulus measured for SON68 glass (83.6 2 GPa) with conventional approaches. Application of the PF-QNM technique will be extended to in situ glass corrosion experiments with the goal of gaining atomic-scale insights into altered layer development by exploiting the mechanical property differences that exist between silica gel (e.g., altered layer) and pristine glass surface.

  19. Lab 6: Forced Harmonic Motion Driven harmonic oscillation

    E-Print Network [OSTI]

    Gustafsson, Torgny

    Lab 6: Forced Harmonic Motion Driven harmonic oscillation Example: Atomic force microscope watch, circuit, ... #12;A constant energy flow at steady state ( )F t dF Rx= - 0oin ut PP + = #12;Forced harmonic t - = + #12;Forced harmonic oscillation (cont.) ( ) ( ) ( ) 0 2 2 0 cos 2 sin cos cosF m

  20. Hidden momentum in a hydrogen atom and the Lorentz force law

    E-Print Network [OSTI]

    J. S. Oliveira Filho; Pablo L. Saldanha

    2015-08-03

    By using perturbation theory, we show that an hydrogen atom with magnetic moment due to the orbital angular momentum of the electron has hidden momentum in the presence of an external electric field. This means that the atomic electronic cloud has a nonzero linear momentum in its center of mass rest frame due to a relativistic effect. This is completely analogous to the hidden momentum that a classical current loop has in the presence of an external electric field. We discuss that this effect is essential for the validity of the Lorentz force law in quantum systems. We also connect our results to the secular Abraham-Minkowski debate about the momentum of light in material media.

  1. Hidden momentum in a hydrogen atom and the Lorentz force law

    E-Print Network [OSTI]

    Filho, J S Oliveira

    2015-01-01

    By using perturbation theory, we show that an hydrogen atom with magnetic moment due to the orbital angular momentum of the electron has hidden momentum in the presence of an external electric field. This means that the atomic electronic cloud has a nonzero linear momentum in its center of mass rest frame due to a relativistic effect. This is completely analogous to the hidden momentum that a classical current loop has in the presence of an external electric field. We discuss that this effect is essential for the validity of the Lorentz force law in quantum systems. We also connect our results to the secular Abraham-Minkowski debate about the momentum of light in material media.

  2. Conductive atomic force microscopy study of local electronic transport in ZnTe thin films

    SciTech Connect (OSTI)

    Kshirsagar, Sachin D.; Krishna, M. Ghanashyam; Tewari, Surya P.

    2013-02-05

    ZnTe thin films obtained by the electron beam evaporation technique were subjected to thermal annealing at 500 Degree-Sign C for 2 hours. The as deposited films were amorphous but transformed to the crystalline state under influence of the thermal treatment. There is increase in optical absorption due to the heat treatment caused by increase in free carrier concentration. Conductive atomic force microscopy shows the presence of electronic inhomogeneities in the films. This is attributed to local compositional variations in the films. I-V analysis in these systems indicates formation of Schottky junction at the metal semiconductor (M-S) interface.

  3. Enhanced efficiency in the excitation of higher modes for atomic force microscopy and mechanical sensors operated in liquids

    SciTech Connect (OSTI)

    Penedo, M., E-mail: mapenedo@imm.cnm.csic.es; Hormeño, S.; Fernández-Martínez, I.; Luna, M.; Briones, F. [IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid (Spain); Raman, A. [Birck Nanotechnology Center and School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47904 (United States)

    2014-10-27

    Recent developments in dynamic Atomic Force Microscopy where several eigenmodes are simultaneously excited in liquid media are proving to be an excellent tool in biological studies. Despite its relevance, the search for a reliable, efficient, and strong cantilever excitation method is still in progress. Herein, we present a theoretical modeling and experimental results of different actuation methods compatible with the operation of Atomic Force Microscopy in liquid environments: ideal acoustic, homogeneously distributed force, distributed applied torque (MAC Mode™), photothermal and magnetostrictive excitation. From the analysis of the results, it can be concluded that magnetostriction is the strongest and most efficient technique for higher eigenmode excitation when using soft cantilevers in liquid media.

  4. Atomic-force microscopy and photoluminescence of nanostructured CdTe

    SciTech Connect (OSTI)

    Babentsov, V.; Sizov, F.; Franc, J.; Luchenko, A.; Svezhentsova, E. Tsybrii, Z.

    2013-09-15

    Low-dimensional CdTe nanorods with a diameter of 10-30 nm and a high aspect ratio that reaches 100 are studied. The nanorods are grown by the physical vapor transport method with the use of Bi precipitates on the substrates. In addition, thin films of closely packed CdTe nanorods with the transverse dimensions {approx}(100-200) nm are grown. Atomic-force microscopy shows that the cross sections of all of the nanorods were hexagonally shaped. By photoluminescence measurements, the inference about the wurtzite structure of CdTe is supported, and the structural quality, electron-phonon coupling, and defects are analyzed. On the basis of recent ab initio calculations, the nature of defects responsible for the formation of deep levels in the CdTe layers and bulk crystals are analyzed.

  5. A serial-kinematic nanopositioner for high-speed atomic force microscopy

    SciTech Connect (OSTI)

    Wadikhaye, Sachin P., E-mail: sachin.wadikhaye@uon.edu.au; Yong, Yuen Kuan; Reza Moheimani, S. O. [School of Electrical Engineering and Computer Science, The University of Newcastle, Callaghan, NSW (Australia)

    2014-10-15

    A flexure-guided serial-kinematic XYZ nanopositioner for high-speed Atomic Force Microscopy is presented in this paper. Two aspects influencing the performance of serial-kinematic nanopositioners are studied in this work. First, mass reduction by using tapered flexures is proposed to increased the natural frequency of the nanopositioner. 25% increase in the natural frequency is achieved due to reduced mass with tapered flexures. Second, a study of possible sensor positioning in a serial-kinematic nanopositioner is presented. An arrangement of sensors for exact estimation of cross-coupling is incorporated in the proposed design. A feedforward control strategy based on phaser approach is presented to mitigate the dynamics and nonlinearity in the system. Limitations in design approach and control strategy are discussed in the Conclusion.

  6. ATOMIC FORCE LITHOGRAPHY OF NANO/MICROFLUIDIC CHANNELS FOR VERIFICATION AND MONITORING OF AQUEOUS SOLUTIONS

    SciTech Connect (OSTI)

    Mendez-Torres, A.; Torres, R.; Lam, P.

    2011-07-15

    The growing interest in the physics of fluidic flow in nanoscale channels, as well as the possibility for high sensitive detection of ions and single molecules is driving the development of nanofluidic channels. The enrichment of charged analytes due to electric field-controlled flow and surface charge/dipole interactions along the channel can lead to enhancement of sensitivity and limits-of-detection in sensor instruments. Nuclear material processing, waste remediation, and nuclear non-proliferation applications can greatly benefit from this capability. Atomic force microscopy (AFM) provides a low-cost alternative for the machining of disposable nanochannels. The small AFM tip diameter (< 10 nm) can provide for features at scales restricted in conventional optical and electron-beam lithography. This work presents preliminary results on the fabrication of nano/microfluidic channels on polymer films deposited on quartz substrates by AFM lithography.

  7. ATOMIC FORCE LITHOGRAPHY OF NANO MICROFLUIDIC CHANNELS FOR VERIFICATION AND MONITORING IN AQUEOUS SOLUTIONS

    SciTech Connect (OSTI)

    Torres, R.; Mendez-Torres, A.; Lam, P.

    2011-06-09

    The growing interest in the physics of fluidic flow in nanoscale channels, as well as the possibility for high sensitive detection of ions and single molecules is driving the development of nanofluidic channels. The enrichment of charged analytes due to electric field-controlled flow and surface charge/dipole interactions along the channel can lead to enhancement of sensitivity and limits-of-detection in sensor instruments. Nuclear material processing, waste remediation, and nuclear non-proliferation applications can greatly benefit from this capability. Atomic force microscopy (AFM) provides a low-cost alternative for the machining of disposable nanochannels. The small AFM tip diameter (< 10 nm) can provide for features at scales restricted in conventional optical and electron-beam lithography. This work presents preliminary results on the fabrication of nano/microfluidic channels on polymer films deposited on quartz substrates by AFM lithography.

  8. Investigation of leakage current paths in n-GaN by conductive atomic force microscopy

    SciTech Connect (OSTI)

    Kim, Bumho; Park, Yongjo, E-mail: yp0520@snu.ac.kr, E-mail: eyoon@snu.ac.kr [Energy Semiconductor Research Center, Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of)] [Energy Semiconductor Research Center, Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of); Moon, Daeyoung; Nanishi, Yasushi [WCU Hybrid Materials Program, Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of)] [WCU Hybrid Materials Program, Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of); Joo, Kisu [Energy Semiconductor Research Center, Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of) [Energy Semiconductor Research Center, Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of); Department of Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon 443-270 (Korea, Republic of); Oh, Sewoung [Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of)] [Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, Young Kuk [Korea Research Institute of Chemical Technology, Daejon 305-600 (Korea, Republic of)] [Korea Research Institute of Chemical Technology, Daejon 305-600 (Korea, Republic of); Yoon, Euijoon, E-mail: yp0520@snu.ac.kr, E-mail: eyoon@snu.ac.kr [Energy Semiconductor Research Center, Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of) [Energy Semiconductor Research Center, Advanced Institutes of Convergence Technology, Seoul National University, Suwon 443-270 (Korea, Republic of); WCU Hybrid Materials Program, Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of); Department of Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon 443-270 (Korea, Republic of); Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2014-03-10

    We have investigated electrical characteristics of leakage current paths in n-GaN layer grown by metal-organic chemical vapor deposition with conductive-atomic force microscopy (C-AFM). The C-AFM mapping shows two kinds of leakage current paths existing in the n-GaN layer: open-core dislocation and pure screw dislocation. From the localized I-V curves measured by C-AFM, we confirmed that the open-core screw dislocation shows more significant leakage current. We explained these results in terms of a modified Schottky band model based on donor states formed by oxygen segregation at the (10?10) sidewall of the open-core screw dislocation.

  9. Atomic Forces from Electronic Energies Via the Hellmann-Feynman Theorem, with Application to Semiconductor (110) Surface Relaxation 

    E-Print Network [OSTI]

    SANKEY, OF; Allen, Roland E.

    1986-01-01

    to yield new information on a num- ber of difficult yet technologically important problems. These include (i) the relaxation and the reconstructed geometries of surfaces and interfaces, and the atomic con- figurations in semiconducting alloys, (ii... VOLUM~ 33, NUMBER 10 15 lVIAY 1986 Atomic forces from electronic energies via the Hellmann-Feynman theorem, with application to semiconductor (110)surface relaxation Otto F. Sankey Department ofPhysics, Arizona State University, Tempe, Arizona 85287...

  10. Electron Microscope Facility

    ScienceCinema (OSTI)

    None

    2010-01-08

    Brookhaven Lab is home to one of only a few Scanning Transmision Electron Microscope (STEM) machines in the world and one of the few that can image single heavy atoms.

  11. Imaging and quantitative data acquisition of biological cell walls with Atomic Force Microscopy and Scanning Acoustic Microscopy

    SciTech Connect (OSTI)

    Tittmann, B. R.; Xi, X.

    2014-09-01

    This chapter demonstrates the feasibility of Atomic Force Microscopy (AFM) and High Frequency Scanning Acoustic Microscopy (HF-SAM) as tools to characterize biological tissues. Both the AFM and the SAM have shown to provide imaging (with different resolution) and quantitative elasticity measuring abilities. Plant cell walls with minimal disturbance and under conditions of their native state have been examined with these two kinds of microscopy. After descriptions of both the SAM and AFM, their special features and the typical sample preparation is discussed. The sample preparation is focused here on epidermal peels of onion scales and celery epidermis cells which were sectioned for the AFM to visualize the inner surface (closest to the plasma membrane) of the outer epidermal wall. The nm-wide cellulose microfibrils orientation and multilayer structure were clearly observed. The microfibril orientation and alignment tend to be more organized in older scales compared with younger scales. The onion epidermis cell wall was also used as a test analog to study cell wall elasticity by the AFM nanoindentation and the SAM V(z) feature. The novelty in this work was to demonstrate the capability of these two techniques to analyze isolated, single layered plant cell walls in their natural state. AFM nanoindentation was also used to probe the effects of Ethylenediaminetetraacetic acid (EDTA), and calcium ion treatment to modify pectin networks in cell walls. The results suggest a significant modulus increase in the calcium ion treatment and a slight decrease in EDTA treatment. To complement the AFM measurements, the HF-SAM was used to obtain the V(z) signatures of the onion epidermis. These measurements were focused on documenting the effect of pectinase enzyme treatment. The results indicate a significant change in the V(z) signature curves with time into the enzyme treatment. Thus AFM and HF-SAM open the door to a systematic nondestructive structure and mechanical property study of complex biological cell walls. A unique feature of this approach is that both microscopes allow the biological samples to be examined in their natural fluid (water) environment.

  12. Nanomechanical and topographical imaging of living cells by Atomic Force Microscopy with colloidal probes

    E-Print Network [OSTI]

    Luca Puricelli; Massimiliano Galluzzi; Carsten Schulte; Alessandro Podestà; Paolo Milani

    2015-02-05

    Atomic Force Microscopy (AFM) has a great potential as a tool to characterize mechanical and morphological properties of living cells; these properties have been shown to correlate with cells' fate and patho-physiological state in view of the development of novel early-diagnostic strategies. Although several reports have described experimental and technical approaches for the characterization of cell elasticity by means of AFM, a robust and commonly accepted methodology is still lacking. Here we show that micrometric spherical probes (also known as colloidal probes) are well suited for performing a combined topographic and mechanical analysis of living cells, with spatial resolution suitable for a complete and accurate mapping of cell morphological and elastic properties, and superior reliability and accuracy in the mechanical measurements with respect to conventional and widely used sharp AFM tips. We address a number of issues concerning the nanomechanical analysis, including the applicability of contact mechanical models and the impact of a constrained contact geometry on the measured elastic modulus (the finite-thickness effect). We have tested our protocol by imaging living PC12 and MDA-MB-231 cells, in order to demonstrate the importance of the correction of the finite-thickness effect and the change in cell elasticity induced by the action of a cytoskeleton-targeting drug.

  13. The unification of the fundamental interaction within Maxwell electromagnetism: Model of hydrogen atom. Gravity as the secondary electric force. Calculation of the unified inertia force

    E-Print Network [OSTI]

    L. Neslusan

    2010-12-28

    Considering two static, electrically charged, elementary particles, we demonstrate a possible way of proving that all known fundamental forces in the nature are the manifestations of the single, unique interaction. We re-define the gauging of integration constants in the Schwarzschild solution of Einstein field equations. We consider the potential energy in this context regardless it is gravitational or electric potential energy. With the newly gauged constants, we sketch how the unique interaction can be described with the help of an appropriate solution of the well-known Maxwell equations. According the solution, there are two zones, in the system of two oppositely charged particles, where the force is oscillating. The first particle can be in a stable, constant distance from the second particle, between the neighbouring regions of repulsion and attraction. In an outer oscillation zone, the corresponding energy levels in the proton-electron systems are identical (on the level of accuracy of values calculated by the Dirac's equations) to some experimentally determined levels in the hydrogen atom. For each system of two particles, there is also the zone with the macroscopic, i.e. monotonous behavior of the force. As well, the solution can be used to demonstrate that the net force between two assemblies consisting each (or at least one) of the same numbers of both positively and negatively charged particles is never zero. A secondary electric force, having the same orientation as the primary electric force between the oppositely charged particles, is always present. It can be identified to the gravity. Finally, the solution of the Maxwell equations can be used to calculate the inertia force of a particle. The consistent formulas for both acting and inertia forces enable to construct the dimensionless (without gravitational constant, permitivity of vacuum, etc.) equation of motion.

  14. Experimental Optical-quality geological calcite was cleaved into fragments. In situ atomic force microscope (AFM) imaging was

    E-Print Network [OSTI]

    Dickinson, J. Thomas

    of scanning (more scanned area at top versus more scanned area at the bottom) so it shows that both the upper equally to growth However, as shown below, the amount of total growth induced by the tip is related, 565-583 (1995). 22 J. I. Drever, The Geochemistry of Natural Waters, 3rd ed. (Prentice Hall, Upper

  15. Nanometer-scale investigations by atomic force microscopy into the effect of different treatments on the surface structure of hair

    E-Print Network [OSTI]

    Durkan, C.; Wang, N.

    2014-09-15

    left behind by commercial products. Methods Atomic Force Microscopy (AFM) and related techniques. Results It can be directly seen that washing hair using commercial hair-care products removes deposits that naturally form on the shaft, revealing... . The factors determining which products a given consumer purchases include the brand, the cost, the scent and the perceived benefit. Hair shafts have traditionally been studied using scanning or transmission electron microscopy (SEM or TEM) 2...

  16. Modeling atomic force microscopy at LiNbO3 surfaces from first-principles

    E-Print Network [OSTI]

    Schmidt, Wolf Gero

    on different atomic tip models interacting with x-cut and z-cut LiNbO3 surfaces are calculated within density 30 years AFM has become a major tool for imaging and manipulating matter at the atomic scale [5]. Due of the converse piezoelectric effect to excite deformations of the sample with a metal-coated tip under alternat

  17. An in-vivo study of electrical charge distribution on the bacterial cell wall by Atomic Force Microscopy in vibrating force mode

    E-Print Network [OSTI]

    Christian Marliere; Samia Dhahri

    2015-04-13

    We report an in-vivo electromechanical Atomic Force Microscopy (AFM) study of charge distribution on the cell wall of Gram plus Rhodococcus wratislaviensis bacteria, naturally adherent to a glass substrate, in physiological conditions. The method presented in this paper relies on a detailed study of AFM approach-retract curves giving the variation of the interaction force versus distance between tip and sample. In addition to classical height and mechanical (as stiffness) data, mapping of local electrical properties, as bacterial surface charge, was proved to be feasible at a spatial resolution better than few tens of nanometers. This innovative method relies on the measurement of the cantilever's surface stress through its deflection far from (higher than 10nm) the repulsive contact zone. The variations of surface stress come from modification of electrical surface charge of the cantilever (as in classical electrocapillary measurements) likely stemming from its charging during contact of both tip and sample electrical double layers. This method offers an important improvement in local electrical and electrochemical measurements at the solid-liquid interface particularly in high-molarity electrolytes when compared to technics focused on the direct use of electrostatic force. It thus opens a new way to directly investigate in-situ biological electrical surface processes involved in numerous practical and fundamental problems as bacterial adhesion, biofilm formation, microbial fuel cell, etc.

  18. Observation of cooperatively enhanced atomic dipole forces from NV centers in optically trapped nanodiamonds

    E-Print Network [OSTI]

    Juan, M L; Besga, B; Brennen, G; Molina-Terriza, G; Volz, T

    2015-01-01

    Since the early work by Ashkin in 1970, optical trapping has become one of the most powerful tools for manipulating small particles, such as micron sized beads or single atoms. The optical trapping mechanism is based on the interaction energy of a dipole and the electric field of the laser light. In atom trapping, the dominant contribution typically comes from the allowed optical transition closest to the laser wavelength, whereas for mesoscopic particles it is given by the bulk polarizability of the material. These two different regimes of optical trapping have coexisted for decades without any direct link, resulting in two very different contexts of applications: one being the trapping of small objects mainly in biological settings, the other one being dipole traps for individual neutral atoms in the field of quantum optics. Here we show that for nanoscale diamond crystals containing artificial atoms, so-called nitrogen vacancy (NV) color centers, both regimes of optical trapping can be observed at the same...

  19. Isolating and moving single atoms using silicon nanocrystals

    DOE Patents [OSTI]

    Carroll, Malcolm S. (Albuquerque, NM)

    2010-09-07

    A method is disclosed for isolating single atoms of an atomic species of interest by locating the atoms within silicon nanocrystals. This can be done by implanting, on the average, a single atom of the atomic species of interest into each nanocrystal, and then measuring an electrical charge distribution on the nanocrystals with scanning capacitance microscopy (SCM) or electrostatic force microscopy (EFM) to identify and select those nanocrystals having exactly one atom of the atomic species of interest therein. The nanocrystals with the single atom of the atomic species of interest therein can be sorted and moved using an atomic force microscope (AFM) tip. The method is useful for forming nanoscale electronic and optical devices including quantum computers and single-photon light sources.

  20. Observation of cooperatively enhanced atomic dipole forces from NV centers in optically trapped nanodiamonds

    E-Print Network [OSTI]

    M. L. Juan; C. Bradac; B. Besga; G. Brennen; G. Molina-Terriza; T. Volz

    2015-11-15

    Since the early work by Ashkin in 1970, optical trapping has become one of the most powerful tools for manipulating small particles, such as micron sized beads or single atoms. The optical trapping mechanism is based on the interaction energy of a dipole and the electric field of the laser light. In atom trapping, the dominant contribution typically comes from the allowed optical transition closest to the laser wavelength, whereas for mesoscopic particles it is given by the bulk polarizability of the material. These two different regimes of optical trapping have coexisted for decades without any direct link, resulting in two very different contexts of applications: one being the trapping of small objects mainly in biological settings, the other one being dipole traps for individual neutral atoms in the field of quantum optics. Here we show that for nanoscale diamond crystals containing artificial atoms, so-called nitrogen vacancy (NV) color centers, both regimes of optical trapping can be observed at the same time even in a noisy liquid environment. For wavelengths in the vicinity of the zero-phonon line transition of the color centers, we observe a significant modification ($10\\%$) of the overall trapping strength. Most remarkably, our experimental findings suggest that owing to the large number of artificial atoms, collective effects greatly contribute to the observed trapping strength modification. Our approach adds the powerful atomic-physics toolbox to the field of nano-manipulation.

  1. On the use of peak-force tapping atomic force microscopy for quantification of the local elastic modulus in hardened cement paste

    SciTech Connect (OSTI)

    Trtik, Pavel, E-mail: pavel.trtik@empa.ch [Empa, Swiss Federal Laboratories for Materials Science and Technology, Duebendorf (Switzerland); Kaufmann, Josef [Empa, Swiss Federal Laboratories for Materials Science and Technology, Duebendorf (Switzerland); Volz, Udo [Bruker Nano GmbH, Mannheim (Germany)

    2012-01-15

    A surface of epoxy-impregnated hardened cement paste was investigated using a novel atomic force microscopy (AFM) imaging mode that allows for the quantitative mapping of the local elastic modulus. The analyzed surface was previously prepared using focussed ion beam milling. The same surface was also characterized by electron microscopy and energy-dispersive X-ray spectroscopy. We demonstrate the capability of this quantitative nanomechanical mapping to provide information on the local distribution of the elastic modulus (from about 1 to about 100 GPa) with a spatial resolution in the range of decananometers, that corresponds to that of low-keV back-scattered electron imaging. Despite some surface roughness which affects the measured nanomechanical properties it is shown that topography, adhesion and Young's modulus can be clearly distinguished. The quantitative mapping of the local elastic modulus is able to discriminate between phases in the cement paste microstructure that cannot be distinguished from the corresponding back-scattered electron images.

  2. Probing the elastic response of microalga Scenedesmus dimorphus in dry and aqueous environments through atomic force microscopy

    SciTech Connect (OSTI)

    Warren, K. M.; Mpagazehe, J. N.; Higgs, C. F., E-mail: prl@andrew.cmu.edu, E-mail: higgs@andrew.cmu.edu [Department of Mechanical Engineering, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, Pennsylvania 15213 (United States); LeDuc, P. R., E-mail: prl@andrew.cmu.edu, E-mail: higgs@andrew.cmu.edu [Department of Mechanical Engineering, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, Pennsylvania 15213 (United States); Departments of Biomedical Engineering and Biological Sciences, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, Pennsylvania 15213 (United States)

    2014-10-20

    With the re-emergence of microalgae as a replacement feedstock for petroleum-derived oils, researchers are working to understand its chemical and mechanical behavior. In this work, the mechanical properties of microalgae, Scenedesmus dimorphus, were investigated at the subcellular level to determine the elastic response of cells that were in an aqueous and dried state using nano-scale indentation through atomic force microscopy. The elastic modulus of single-celled S. dimorphus cells increased over tenfold from an aqueous state to a dried state, which allows us to better understand the biophysical response of microalgae to stress.

  3. Imaging and measuring the biophysical properties of Fc gamma receptors on single macrophages using atomic force microscopy

    SciTech Connect (OSTI)

    Li, Mi; University of Chinese Academy of Sciences, Beijing 100049 ; Liu, Lianqing; Xi, Ning; Wang, Yuechao; Xiao, Xiubin; Zhang, Weijing

    2013-09-06

    Highlights: •Nanoscale cellular ultra-structures of macrophages were observed. •The binding affinities of Fc?Rs were measured directly on macrophages. •The nanoscale distributions of Fc?Rs were mapped on macrophages. -- Abstract: Fc gamma receptors (Fc?R), widely expressed on effector cells (e.g., NK cells, macrophages), play an important role in clinical cancer immunotherapy. The binding of Fc?Rs to the Fc portions of antibodies that are attached to the target cells can activate the antibody-dependent cell-mediated cytotoxicity (ADCC) killing mechanism which leads to the lysis of target cells. In this work, we used atomic force microscopy (AFM) to observe the cellular ultra-structures and measure the biophysical properties (affinity and distribution) of Fc?Rs on single macrophages in aqueous environments. AFM imaging was used to obtain the topographies of macrophages, revealing the nanoscale cellular fine structures. For molecular interaction recognition, antibody molecules were attached onto AFM tips via a heterobifunctional polyethylene glycol (PEG) crosslinker. With AFM single-molecule force spectroscopy, the binding affinities of Fc?Rs were quantitatively measured on single macrophages. Adhesion force mapping method was used to localize the Fc?Rs, revealing the nanoscale distribution of Fc?Rs on local areas of macrophages. The experimental results can improve our understanding of Fc?Rs on macrophages; the established approach will facilitate further research on physiological activities involved in antibody-based immunotherapy.

  4. Microscope collision protection apparatus

    DOE Patents [OSTI]

    DeNure, Charles R. (Pocatello, ID)

    2001-10-23

    A microscope collision protection apparatus for a remote control microscope which protects the optical and associated components from damage in the event of an uncontrolled collision with a specimen, regardless of the specimen size or shape. In a preferred embodiment, the apparatus includes a counterbalanced slide for mounting the microscope's optical components. This slide replaces the rigid mounts on conventional upright microscopes with a precision ball bearing slide. As the specimen contacts an optical component, the contacting force will move the slide and the optical components mounted thereon. This movement will protect the optical and associated components from damage as the movement causes a limit switch to be actuated, thereby stopping all motors responsible for the collision.

  5. Multifrequency imaging in the intermittent contact mode of atomic force microscopy: beyond phase imaging

    SciTech Connect (OSTI)

    Guo, Senli; Santiago, Solares D; Mochalin, Vadym; Neitzel, Ioannis; Gogotsi, Yury G.; Kalinin, Sergei V; Jesse, Stephen

    2012-01-01

    Force-based scanning probe microscopies have emerged as a mainstay for probing structural and mechanical properties of materials on the nanometer and molecular scales. Despite tremendous progress achieved to date, the cantilever dynamics in single frequency scanning probe microscopies (SPM) is undefined due to having only two output variables. Here we demonstrate on diamond nanoparticles with different functionalization layers that the use of broad band detection by multiple frequency SPM allows complete information on tip-surface interactions in intermittent contact SPM to be acquired. The obtained data allows sub-3nm resolution even in ambient environment. By tuning the strength of tip-surface interaction, the information on surface state can be obtained.

  6. True atomic-scale imaging of a spinel Li{sub 4}Ti{sub 5}O{sub 12}(111) surface in aqueous solution by frequency-modulation atomic force microscopy

    SciTech Connect (OSTI)

    Kitta, Mitsunori, E-mail: m-kitta@aist.go.jp; Kohyama, Masanori [Research Institute for Ubiquitous Energy Devices, National Institute of Advanced Industrial Science and Technology, 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan); Onishi, Hiroshi [Department of Chemistry, Graduate School of Science, Kobe University 1-1 Rokkodai, Nada, Kobe 657-8501 (Japan)

    2014-09-15

    Spinel-type lithium titanium oxide (LTO; Li{sub 4}Ti{sub 5}O{sub 12}) is a negative electrode material for lithium-ion batteries. Revealing the atomic-scale surface structure of LTO in liquid is highly necessary to investigate its surface properties in practical environments. Here, we reveal an atomic-scale image of the LTO(111) surface in LiCl aqueous solution using frequency-modulation atomic force microscopy. Atomically flat terraces and single steps having heights of multiples of 0.5?nm were observed in the aqueous solution. Hexagonal bright spots separated by 0.6?nm were also observed on the flat terrace part, corresponding to the atomistic contrast observed in the ultrahigh vacuum condition, which suggests that the basic atomic structure of the LTO(111) surface is retained without dramatic reconstruction even in the aqueous solution.

  7. Demonstration of the Lateral Casimir Force

    E-Print Network [OSTI]

    F. Chen; U. Mohideen; G. L. Klimchitskaya; V. M. Mostepanenko

    2002-01-19

    The lateral Casimir force between a sinusoidally corrugated gold coated plate and large sphere was measured for surface separations between 0.2 $\\mu$m to 0.3 $\\mu$m using an atomic force microscope. The measured force shows the required periodicity corresponding to the corrugations. It also exhibits the necessary inverse fourth power distance dependence. The obtained results are shown to be in good agreement with a complete theory taking into account the imperfectness of the boundary metal. This demonstration opens new opportunities for the use of the Casimir effect for lateral translation in microelectromechanical systems.

  8. Growth direction and morphology of ZnO nanobelts revealed by combining in situ atomic force microscopy and polarized Raman spectroscopy

    E-Print Network [OSTI]

    Wang, Zhong L.

    Growth direction and morphology of ZnO nanobelts revealed by combining in situ atomic force of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, USA 2 School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, USA Received 26 June 2009; revised

  9. Selection of higher eigenmode amplitude based on dissipated power and virial contrast in bimodal atomic force microscopy

    SciTech Connect (OSTI)

    Diaz, Alfredo J.; Eslami, Babak; López-Guerra, Enrique A.; Solares, Santiago D., E-mail: ssolares@gwu.edu [Department of Mechanical Engineering, University of Maryland, College Park, Maryland 20742 (United States)

    2014-09-14

    This paper explores the effect of the amplitude ratio of the higher to the fundamental eigenmode in bimodal atomic force microscopy (AFM) on the phase contrast and the dissipated power contrast of the higher eigenmode. We explore the optimization of the amplitude ratio in order to maximize the type of contrast that is most relevant to the particular study. Specifically, we show that the trends in the contrast range behave differently for different quantities, especially the dissipated power and the phase, with the former being more meaningful than the latter (a similar analysis can be carried out using the virial, for which we also provide a brief example). Our work is based on numerical simulations using two different conservative-dissipative tip-sample models, including the standard linear solid and the combination of a dissipation coefficient with a conservative model, as well as experimental images of thin film Nafion{sup ®} proton exchange polymers. We focus on the original bimodal AFM method, where the higher eigenmode is driven with constant amplitude and frequency (i.e., in “open loop”).

  10. PUBLISHED ONLINE: 20 MARCH 2011 | DOI: 10.1038/NPHYS1954 A synthetic electric force acting on neutral atoms

    E-Print Network [OSTI]

    Loss, Daniel

    energy in a rubidium Bose­ Einstein condensate: the neutral atoms behave as charged particles do Hamiltonians of this form for ultracold atoms, and prepared a Bose­Einstein condensate (BEC) at rest

  11. Direct observation of electron emission from the grain boundaries of chemical vapour deposition diamond films by tunneling atomic force microscopy

    SciTech Connect (OSTI)

    Chatterjee, Vijay; Harniman, Robert; May, Paul W.; Barhai, P. K.

    2014-04-28

    The emission of electrons from diamond in vacuum occurs readily as a result of the negative electron affinity of the hydrogenated surface due to features with nanoscale dimensions, which can concentrate electric fields high enough to induce electron emission from them. Electrons can be emitted as a result of an applied electric field (field emission) with possible uses in displays or cold-cathode devices. Alternatively, electrons can be emitted simply by heating the diamond in vacuum to temperatures as low as 350?°C (thermionic emission), and this may find applications in solar energy generation or energy harvesting devices. Electron emission studies usually use doped polycrystalline diamond films deposited onto Si or metallic substrates by chemical vapor deposition, and these films have a rough, faceted morphology on the micron or nanometer scale. Electron emission is often improved by patterning the diamond surface into sharp points or needles, the idea being that the field lines concentrate at the points lowering the barrier for electron emission. However, there is little direct evidence that electrons are emitted from these sharp tips. The few reports in the literature that have studied the emission sites suggested that emission came from the grain boundaries and not the protruding regions. We now present direct observation of the emission sites over a large area of polycrystalline diamond using tunneling atomic force microscopy. We confirm that the emission current comes mostly from the grain boundaries, which is consistent with a model for emission in which the non-diamond phase is the source of electrons with a threshold that is determined by the surrounding hydrogenated diamond surface.

  12. An improved proximity force approximation for electrostatics

    E-Print Network [OSTI]

    C. D. Fosco; F. C. Lombardo; F. D. Mazzitelli

    2012-04-23

    A quite straightforward approximation for the electrostatic interaction between two perfectly conducting surfaces suggests itself when the distance between them is much smaller than the characteristic lengths associated to their shapes. Indeed, in the so called "proximity force approximation" the electrostatic force is evaluated by first dividing each surface into a set of small flat patches, and then adding up the forces due two opposite pairs, the contribution of which are approximated as due to pairs of parallel planes. This approximation has been widely and successfully applied to different contexts, ranging from nuclear physics to Casimir effect calculations. We present here an improvement on this approximation, based on a derivative expansion for the electrostatic energy contained between the surfaces. The results obtained could be useful to discuss the geometric dependence of the electrostatic force, and also as a convenient benchmark for numerical analyses of the tip-sample electrostatic interaction in atomic force microscopes.

  13. Switchable stiffness scanning microscope probe

    E-Print Network [OSTI]

    Mueller-Falcke, Clemens T. (Clemens Tobias)

    2005-01-01

    Atomic Force Microscopy (AFM) has rapidly gained widespread utilization as an imaging device and micro/nano-manipulator during recent years. This thesis investigates the new concept of a dual stiffness scanning probe with ...

  14. The Microscopic Linear Dynamics

    E-Print Network [OSTI]

    Penny, Will

    The Microscopic Brain Will Penny Linear Dynamics Exponentials Matrix Exponential Eigendecomposition References The Microscopic Brain Will Penny 7th April 2011 #12;The Microscopic Brain Will Penny Linear;The Microscopic Brain Will Penny Linear Dynamics Exponentials Matrix Exponential Eigendecomposition

  15. Velocity tuning of friction with two trapped atoms

    E-Print Network [OSTI]

    Gangloff, Dorian; Counts, Ian; Jhe, Wonho; Vuleti?, Vladan

    2015-01-01

    Friction is the basic, ubiquitous mechanical interaction between two surfaces that results in resistance to motion and energy dissipation. In spite of its technological and economic significance, our ability to control friction remains modest, and our understanding of the microscopic processes incomplete. At the atomic scale, mismatch between the two contacting crystal lattices can lead to a reduction of stick-slip friction (structural lubricity), while thermally activated atomic motion can give rise to a complex velocity dependence, and nearly vanishing friction at sufficiently low velocities (thermal lubricity). Atomic force microscopy has provided a wealth of experimental results, but limitations in the dynamic range, time resolution, and control at the single-atom level have hampered a full quantitative description from first principles. Here, using an ion-crystal friction emulator with single-atom, single substrate-site spatial resolution and single-slip temporal resolution, we measure the friction force...

  16. Surface characterization of silica glass substrates treated by atomic hydrogen

    SciTech Connect (OSTI)

    Inoue, Hiroyuki [Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo 153-8505 (Japan); Masuno, Atsunobu, E-mail: masuno@iis.u-tokyo.ac.jp [Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo 153-8505 (Japan); Ishibashi, Keiji [Canon ANELVA Corporation, Asao-ku, Kawasaki, Kanagawa 215-8550 (Japan); Tawarayama, Hiromasa [Kawazoe Frontier Technologies Corporation, Kuden 931-113, Sakae-ku, Yokohama, Kanagawa 247-0014 (Japan); Zhang, Yingjiu; Utsuno, Futoshi [Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo 153-8505 (Japan); Koya, Kazuo; Fujinoki, Akira [Shin Etsu Quartz Prod. Co., Ltd., Res and Applicat Lab, Fukushima 963-0725 (Japan); Kawazoe, Hiroshi [Kawazoe Frontier Technologies Corporation, Kuden 931-113, Sakae-ku, Yokohama, Kanagawa 247-0014 (Japan)

    2013-12-15

    Silica glass substrates with very flat surfaces were exposed to atomic hydrogen at different temperatures and durations. An atomic force microscope was used to measure root-mean-square (RMS) roughness and two-dimensional power spectral density (PSD). In the treatment with atomic hydrogen up to 900 °C, there was no significant change in the surface. By the treatment at 1000 °C, the changes in the RMS roughness and the PSD curves were observed. It was suggested that these changes were caused by etching due to reactions of atomic hydrogen with surface silica. By analysis based on the k-correlation model, it was found that the spatial frequency of the asperities became higher with an increase of the treatment time. Furthermore, the data showed that atomic hydrogen can flatten silica glass surfaces by controlling heat-treatment conditions. - Highlights: • Silica glass surface was treated by atomic hydrogen at various temperatures. • Surface roughness was measured by an atomic force microscope. • Roughness data were analyzed by two-dimensional power spectral density. • Atomic hydrogen can flatten silica glass surfaces.

  17. An improved proximity force approximation for electrostatics

    SciTech Connect (OSTI)

    Fosco, Cesar D.; Instituto Balseiro, Universidad Nacional de Cuyo, R8402AGP Bariloche ; Lombardo, Fernando C.; IFIBA ; Mazzitelli, Francisco D.

    2012-08-15

    A quite straightforward approximation for the electrostatic interaction between two perfectly conducting surfaces suggests itself when the distance between them is much smaller than the characteristic lengths associated with their shapes. Indeed, in the so called 'proximity force approximation' the electrostatic force is evaluated by first dividing each surface into a set of small flat patches, and then adding up the forces due two opposite pairs, the contributions of which are approximated as due to pairs of parallel planes. This approximation has been widely and successfully applied in different contexts, ranging from nuclear physics to Casimir effect calculations. We present here an improvement on this approximation, based on a derivative expansion for the electrostatic energy contained between the surfaces. The results obtained could be useful for discussing the geometric dependence of the electrostatic force, and also as a convenient benchmark for numerical analyses of the tip-sample electrostatic interaction in atomic force microscopes. - Highlights: Black-Right-Pointing-Pointer The proximity force approximation (PFA) has been widely used in different areas. Black-Right-Pointing-Pointer The PFA can be improved using a derivative expansion in the shape of the surfaces. Black-Right-Pointing-Pointer We use the improved PFA to compute electrostatic forces between conductors. Black-Right-Pointing-Pointer The results can be used as an analytic benchmark for numerical calculations in AFM. Black-Right-Pointing-Pointer Insight is provided for people who use the PFA to compute nuclear and Casimir forces.

  18. A non-contact, thermal noise based method for the calibration of lateral deflection sensitivity in atomic force microscopy

    SciTech Connect (OSTI)

    Mullin, Nic Hobbs, Jamie K.

    2014-11-15

    Calibration of lateral forces and displacements has been a long standing problem in lateral force microscopies. Recently, it was shown by Wagner et al. that the thermal noise spectrum of the first torsional mode may be used to calibrate the deflection sensitivity of the detector. This method is quick, non-destructive and may be performed in situ in air or liquid. Here we make a full quantitative comparison of the lateral inverse optical lever sensitivity obtained by the lateral thermal noise method and the shape independent method developed by Anderson et al. We find that the thermal method provides accurate results for a wide variety of rectangular cantilevers, provided that the geometry of the cantilever is suitable for torsional stiffness calibration by the torsional Sader method, in-plane bending of the cantilever may be eliminated or accounted for and that any scaling of the lateral deflection signal between the measurement of the lateral thermal noise and the measurement of the lateral deflection is eliminated or corrected for. We also demonstrate that the thermal method may be used to characterize the linearity of the detector signal as a function of position, and find a deviation of less than 8% for the instrument used.

  19. Cross-Sectional Conductive Atomic Force Microscopy of CdTe/CdS Solar Cells: Effects of Etching and Back-Contact Processes; Preprint

    SciTech Connect (OSTI)

    Moutinho, H. R.; Dhere, R. G.; Jiang, C.-S.; Gessert, T. A.; Duda, A. M.; Young, M.; Metzger, W. K.; Li, X.; Al-Jassim, M. M.

    2006-05-01

    We investigated the effects of the etching processes using bromine and nitric-phosphoric acid solutions, as well as of Cu, in the bulk electrical conductivity of CdTe/CdS solar cells using conductive atomic force microscopy (C-AFM). Although the etching process can create a conductive layer on the surface of the CdTe, the layer is very shallow. In contrast, the addition of a thin layer of Cu to the surface creates a conductive layer inside the CdTe that is not uniform in depth, is concentrated at grains boundaries, and may short circuit the device if the CdTe is too thin. The etching process facilitates the Cu diffusion and results in thicker conductive layers. The existence of this inhomogeneous conductive layer directly affects the current transport and is probably the reason for needing thick CdTe in these devices.

  20. Ultra low-K shrinkage behavior when under electron beam in a scanning electron microscope

    SciTech Connect (OSTI)

    Lorut, F.; Imbert, G. [ST Microelectronics, 850 rue Jean Monnet, 38926 Crolles Cedex (France)] [ST Microelectronics, 850 rue Jean Monnet, 38926 Crolles Cedex (France); Roggero, A. [Centre National d'Etudes Spatiales, 18 Avenue Edouard Belin, 31400 Toulouse (France)] [Centre National d'Etudes Spatiales, 18 Avenue Edouard Belin, 31400 Toulouse (France)

    2013-08-28

    In this paper, we investigate the tendency of porous low-K dielectrics (also named Ultra Low-K, ULK) behavior to shrink when exposed to the electron beam of a scanning electron microscope. Various experimental electron beam conditions have been used for irradiating ULK thin films, and the resulting shrinkage has been measured through use of an atomic force microscope tool. We report the shrinkage to be a fast, cumulative, and dose dependent effect. Correlation of the shrinkage with incident electron beam energy loss has also been evidenced. The chemical modification of the ULK films within the interaction volume has been demonstrated, with a densification of the layer and a loss of carbon and hydrogen elements being observed.

  1. Cryogenic immersion microscope

    DOE Patents [OSTI]

    Le Gros, Mark (Berkeley, CA); Larabell, Carolyn A. (Berkeley, CA)

    2010-12-14

    A cryogenic immersion microscope whose objective lens is at least partially in contact with a liquid reservoir of a cryogenic liquid, in which reservoir a sample of interest is immersed is disclosed. When the cryogenic liquid has an index of refraction that reduces refraction at interfaces between the lens and the sample, overall resolution and image quality are improved. A combination of an immersion microscope and x-ray microscope, suitable for imaging at cryogenic temperatures is also disclosed.

  2. Characterization of grain boundary conductivity of spin-sprayed ferrites using scanning microwave microscope

    SciTech Connect (OSTI)

    Myers, J.; Nicodemus, T.; Zhuang, Y., E-mail: yan.zhuang@wright.edu [Department of Electrical Engineering, Wright State University, Dayton, Ohio 45435 (United States); Watanabe, T.; Matsushita, N. [Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama (Japan); Yamaguchi, M. [Department of Electrical Engineering, Tohoku University, Sendai 980-8579 (Japan)

    2014-05-07

    Grain boundary electrical conductivity of ferrite materials has been characterized using scanning microwave microscope. Structural, electrical, and magnetic properties of Fe{sub 3}O{sub 4} spin-sprayed thin films onto glass substrates for different length of growth times were investigated using a scanning microwave microscope, an atomic force microscope, a four-point probe measurement, and a made in house transmission line based magnetic permeameter. The real part of the magnetic permeability shows almost constant between 10 and 300?MHz. As the Fe{sub 3}O{sub 4} film thickness increases, the grain size becomes larger, leading to a higher DC conductivity. However, the loss in the Fe{sub 3}O{sub 4} films at high frequency does not increase correspondingly. By measuring the reflection coefficient s{sub 11} from the scanning microwave microscope, it turns out that the grain boundaries of the Fe{sub 3}O{sub 4} films exhibit higher electric conductivity than the grains, which contributes loss at radio frequencies. This result will provide guidance for further improvement of low loss ferrite materials for high frequency applications.

  3. Dislocation dynamics: from microscopic models to macroscopic crystal plasticity

    E-Print Network [OSTI]

    El Hajj, Ahmad

    Dislocation dynamics: from microscopic models to macroscopic crystal plasticity A. El Hajj , H study ranges from atomic models to macroscopic crystal plasticity. At each scale, dislocations can crystal Z3 where each position with integer coordinates is occupied by one atom. We want to describe

  4. Infrared microscope inspection apparatus

    DOE Patents [OSTI]

    Forman, S.E.; Caunt, J.W.

    1985-02-26

    Apparatus and system for inspecting infrared transparents, such as an array of photovoltaic modules containing silicon solar cells, includes an infrared microscope, at least three sources of infrared light placed around and having their axes intersect the center of the object field and means for sending the reflected light through the microscope. The apparatus is adapted to be mounted on an X-Y translator positioned adjacent the object surface. 4 figs.

  5. Infrared microscope inspection apparatus

    DOE Patents [OSTI]

    Forman, Steven E. (Framingham, MA); Caunt, James W. (Concord, MA)

    1985-02-26

    Apparatus and system for inspecting infrared transparents, such as an array of photovoltaic modules containing silicon solar cells, includes an infrared microscope, at least three sources of infrared light placed around and having their axes intersect the center of the object field and means for sending the reflected light through the microscope. The apparatus is adapted to be mounted on an X-Y translator positioned adjacent the object surface.

  6. Development of a quartz tuning-fork-based force sensor for measurements in the tens of nanoNewton force range during nanomanipulation experiments

    SciTech Connect (OSTI)

    Oiko, V. T. A. Rodrigues, V.; Ugarte, D.; Martins, B. V. C.; Silva, P. C.

    2014-03-15

    Understanding the mechanical properties of nanoscale systems requires new experimental and theoretical tools. In particular, force sensors compatible with nanomechanical testing experiments and with sensitivity in the nN range are required. Here, we report the development and testing of a tuning-fork-based force sensor for in situ nanomanipulation experiments inside a scanning electron microscope. The sensor uses a very simple design for the electronics and it allows the direct and quantitative force measurement in the 1–100 nN force range. The sensor response is initially calibrated against a nN range force standard, as, for example, a calibrated Atomic Force Microscopy cantilever; subsequently, applied force values can be directly derived using only the electric signals generated by the tuning fork. Using a homemade nanomanipulator, the quantitative force sensor has been used to analyze the mechanical deformation of multi-walled carbon nanotube bundles, where we analyzed forces in the 5–40 nN range, measured with an error bar of a few nN.

  7. PAPER www.rsc.org/loc | Lab on a Chip Open micro-fluidic system for atomic force microscopy-guided in situ

    E-Print Network [OSTI]

    by light harvesting complexes, which funnel that energy into the reaction centers of the photosynthetic electron transport chain, causing a charge separation that provides the driving force to split water cells and has the potential to be exploited by direct extraction of energetic electrons from

  8. Ion photon emission microscope

    DOE Patents [OSTI]

    Doyle, Barney L. (Albuquerque, NM)

    2003-04-22

    An ion beam analysis system that creates microscopic multidimensional image maps of the effects of high energy ions from an unfocussed source upon a sample by correlating the exact entry point of an ion into a sample by projection imaging of the ion-induced photons emitted at that point with a signal from a detector that measures the interaction of that ion within the sample. The emitted photons are collected in the lens system of a conventional optical microscope, and projected on the image plane of a high resolution single photon position sensitive detector. Position signals from this photon detector are then correlated in time with electrical effects, including the malfunction of digital circuits, detected within the sample that were caused by the individual ion that created these photons initially.

  9. Electron microscope phase enhancement

    DOE Patents [OSTI]

    Jin, Jian; Glaeser, Robert M.

    2010-06-15

    A microfabricated electron phase shift element is used for modifying the phase characteristics of an electron beam passing though its center aperture, while not affecting the more divergent portion of an incident beam to selectively provide a ninety-degree phase shift to the unscattered beam in the back focal plan of the objective lens, in order to realize Zernike-type, in-focus phase contrast in an electron microscope. One application of the element is to increase the contrast of an electron microscope for viewing weakly scattering samples while in focus. Typical weakly scattering samples include biological samples such as macromolecules, or perhaps cells. Preliminary experimental images demonstrate that these devices do apply a ninety degree phase shift as expected. Electrostatic calculations have been used to determine that fringing fields in the region of the scattered electron beams will cause a negligible phase shift as long as the ratio of electrode length to the transverse feature-size aperture is about 5:1. Calculations are underway to determine the feasibility of aspect smaller aspect ratios of about 3:1 and about 2:1.

  10. Microscopic calculations in asymmetric nuclear matter

    E-Print Network [OSTI]

    D. Alonso; F. Sammarruca

    2003-02-06

    A microscopic calculation of the equation of state for asymmetric nuclear matter is presented. We employ realistic nucleon-nucleon forces and operate within the Dirac-Brueckner-Hartree-Fock approach to nuclear matter. The focal point of this paper is a (momentum-space) G-matrix which properly accounts for the asymmetry between protons and neutrons. This will merge naturally into the development of an effective interaction suitable for applications to asymmetric nuclei, which will be the object of extensive study in the future.

  11. Climate forcing Climate forcing

    E-Print Network [OSTI]

    MacKinnon, Jennifer

    parameters (solar distance factors) solar luminosity moon orbit volcanoes and other geothermal sources,000 years (large panels) and since 1750 (inset panels). Measurements are shown from ice cores (symbols forcings are shown on the right hand axes of the large panels. {Figure 6.4} !"#$#%&'(!&#)$&*$+#$,-.$/0

  12. Experimental Free Energy Surface Reconstruction From Single-Molecule Force Spectroscopy Using Jarzynski's Equality

    E-Print Network [OSTI]

    Nolan C. Harris; Yang Song; Ching-Hwa Kiang

    2007-07-03

    We used the atomic force microscope to manipulate and unfold individual molecules of the titin I27 domain and reconstructed its free energy surface using Jarzynski's equality. The free energy surface for both stretching and unfolding was reconstructed using an exact formula that relates the nonequilibrium work fluctuations to the molecular free energy. In addition, the unfolding free energy barrier, i.e. the activation energy, was directly obtained from experimental data for the first time. This work demonstrates that Jarzynski's equality can be used to analyze nonequilibrium single-molecule experiments, and to obtain the free energy surfaces for molecular systems, including interactions for which only nonequilibrium work can be measured.

  13. Femtosecond photoelectron point projection microscope

    SciTech Connect (OSTI)

    Quinonez, Erik; Handali, Jonathan; Barwick, Brett

    2013-10-15

    By utilizing a nanometer ultrafast electron source in a point projection microscope we demonstrate that images of nanoparticles with spatial resolutions of the order of 100 nanometers can be obtained. The duration of the emission process of the photoemitted electrons used to make images is shown to be of the order of 100 fs using an autocorrelation technique. The compact geometry of this photoelectron point projection microscope does not preclude its use as a simple ultrafast electron microscope, and we use simple analytic models to estimate temporal resolutions that can be expected when using it as a pump-probe ultrafast electron microscope. These models show a significant increase in temporal resolution when comparing to ultrafast electron microscopes based on conventional designs. We also model the microscopes spectroscopic abilities to capture ultrafast phenomena such as the photon induced near field effect.

  14. Imaging arrangement and microscope

    DOE Patents [OSTI]

    Pertsinidis, Alexandros; Chu, Steven

    2015-12-15

    An embodiment of the present invention is an imaging arrangement that includes imaging optics, a fiducial light source, and a control system. In operation, the imaging optics separate light into first and second tight by wavelength and project the first and second light onto first and second areas within first and second detector regions, respectively. The imaging optics separate fiducial light from the fiducial light source into first and second fiducial light and project the first and second fiducial light onto third and fourth areas within the first and second detector regions, respectively. The control system adjusts alignment of the imaging optics so that the first and second fiducial light projected onto the first and second detector regions maintain relatively constant positions within the first and second detector regions, respectively. Another embodiment of the present invention is a microscope that includes the imaging arrangement.

  15. Transmission electron microscope CCD camera

    DOE Patents [OSTI]

    Downing, Kenneth H. (Lafayette, CA)

    1999-01-01

    In order to improve the performance of a CCD camera on a high voltage electron microscope, an electron decelerator is inserted between the microscope column and the CCD. This arrangement optimizes the interaction of the electron beam with the scintillator of the CCD camera while retaining optimization of the microscope optics and of the interaction of the beam with the specimen. Changing the electron beam energy between the specimen and camera allows both to be optimized.

  16. Casimir and van der Waals forces: Advances and problems

    E-Print Network [OSTI]

    G. L. Klimchitskaya; V. M. Mostepanenko

    2015-07-09

    We review modern achievements and problems in physics of the van der Waals and Casimir forces which arise due to zero-point and thermal fluctuations of the electromagnetic field between closely spaced material surfaces. This subject attracted great experimental and theoretical attention during the last few years because the fluctuation-induced forces find a lot of applications in both fundamental physics and nanotechnology. After a short introduction to the subject, we describe main experimental and theoretical results obtained in the field during the last fifteen years. In the following presentation, we discuss some of the recent results by the authors and their collaborators which are of high promise for future developments. Specifically, we consider new features of the Casimir force acting between a gold sphere and an indium tin oxide plate, present the experimental and theoretical results on measuring the Casimir interaction between two gold surfaces by means of dynamic atomic force microscope, and outline first measurements of the Casimir interaction between magnetic surfaces and related theory. Special attention is devoted to the Casimir effect for graphene, which is the prospective material for microelectromechanical devices of next generations.

  17. Metal atomization spray nozzle

    DOE Patents [OSTI]

    Huxford, T.J.

    1993-11-16

    A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal. 6 figures.

  18. Calibration of an interfacial force microscope for MEMS metrology...

    Office of Scientific and Technical Information (OSTI)

    performance during each iteration of design. Once a design is finalized, suitable tools are needed to provide quality assurance for manufactured devices. To ensure device...

  19. Nonlocal microscopic theory of Casimir forces at finite temperature

    SciTech Connect (OSTI)

    Despoja, V.; Marusic, L.

    2011-04-15

    The interaction energy between two metallic slabs in the retarded limit at finite temperature is expressed in terms of surface polariton propagators for separate slabs, avoiding the usual matching procedure, with both diamagnetic and paramagnetic excitations included correctly. This enables appropriate treatment of arbitrary electron density profiles and fully nonlocal electronic response, including both collective and single-particle excitations. The results are verified by performing the nonretarded and long-wavelength (local) limits and showing that they reduce to the previously obtained expressions. Possibilities for practical use of the theory are explored by applying it to calculation of various contributions to the Casimir energy between two silver slabs.

  20. Effect of current compliance and voltage sweep rate on the resistive switching of HfO{sub 2}/ITO/Invar structure as measured by conductive atomic force microscopy

    SciTech Connect (OSTI)

    Wu, You-Lin Liao, Chun-Wei; Ling, Jing-Jenn

    2014-06-16

    The electrical characterization of HfO{sub 2}/ITO/Invar resistive switching memory structure was studied using conductive atomic force microscopy (AFM) with a semiconductor parameter analyzer, Agilent 4156C. The metal alloy Invar was used as the metal substrate to ensure good ohmic contact with the substrate holder of the AFM. A conductive Pt/Ir AFM tip was placed in direct contact with the HfO{sub 2} surface, such that it acted as the top electrode. Nanoscale current-voltage (I-V) characteristics of the HfO{sub 2}/ITO/Invar structure were measured by applying a ramp voltage through the conductive AFM tip at various current compliances and ramp voltage sweep rates. It was found that the resistance of the low resistance state (RLRS) decreased with increasing current compliance value, but resistance of high resistance state (RHRS) barely changed. However, both the RHRS and RLRS decreased as the voltage sweep rate increased. The reasons for this dependency on current compliance and voltage sweep rate are discussed.

  1. Chemistry 365: Force Constant Calculations David Ronis

    E-Print Network [OSTI]

    Ronis, David M.

    cost energy, and hence, there will no force in thy y or z directions (thereby resulting in 4 zero eigenChemistry 365: Force Constant Calculations © David Ronis McGill University Here is an example of a force constant matrix calculation. We will consider a diatomic molecule, where the two atoms interact

  2. Circular dichroism in the electron microscope: Progress and applications (invited)

    SciTech Connect (OSTI)

    Schattschneider, P.; Loeffler, S.; Ennen, I.; Stoeger-Pollach, M.; Verbeeck, J.

    2010-05-15

    According to theory, x-ray magnetic circular dichroism in a synchrotron is equivalent to energy loss magnetic chiral dichroism (EMCD) in a transmission electron microscope (TEM). After a synopsis of the development of EMCD, the theoretical background is reviewed and recent results are presented, focusing on the study of magnetic nanoparticles for ferrofluids and Heusler alloys for spintronic devices. Simulated maps of the dichroic strength as a function of atom position in the crystal allow evaluating the influence of specimen thickness and sample tilt on the experimental EMCD signal. Finally, the possibility of direct observation of chiral electronic transitions with atomic resolution in a TEM is discussed.

  3. Controlled nanostructure fabrication using atomic force microscopy 

    E-Print Network [OSTI]

    Sapcharoenkun, Chaweewan

    2013-06-29

    Scanning probe microscopy (SPM) nanolithography has been found to be a powerful and low-cost approach for sub-100 nm patterning. In this thesis, the possibility of using a state-of-the-art SPM system to controllably ...

  4. Mean field extrapolations of microscopic nuclear equations of state

    E-Print Network [OSTI]

    Rrapaj, Ermal; Holt, Jeremy W

    2015-01-01

    We explore the use of mean field models to approximate microscopic nuclear equations of state derived from chiral effective field theory across the densities and temperatures relevant for simulating astrophysical phenomena such as core-collapse supernovae and binary neutron star mergers. We consider both relativistic mean field theory with scalar and vector meson exchange as well as energy density functionals based on Skyrme phenomenology and compare to thermodynamic equations of state derived from chiral two- and three-nucleon forces in many-body perturbation theory. Quantum Monte Carlo simulations of symmetric nuclear matter and pure neutron matter are used to determine the density regimes in which perturbation theory with chiral nuclear forces is valid. Within the theoretical uncertainties associated with the many-body methods, we find that select mean field models describe well microscopic nuclear thermodynamics. As an additional consistency requirement, we study as well the single-particle properties of ...

  5. Atomic force microscopy and x-ray photoelectron spectroscopy investigations of the morphology and chemistry of a PdCl{sub 2}/SnCl{sub 2} electroless plating catalysis system adsorbed onto shape memory alloy particles

    SciTech Connect (OSTI)

    Silvain, J.F.; Fouassier, O.; Lescaux, S. [Institut de Chimie de la Matiere Condensee de Bordeaux (ICMCB) - CNRS, Universite de Bordeaux 1, 87 Avenue du Dr A. Schweitzer, F-33608 PESSAC (France); Veeco, Z.I. de la Gaudree, 11 Rue Marie Poussepin, F-91412 Dourdain (France)

    2004-11-01

    A study of the different stages of the electroless deposition of copper on micronic NiTi shape memory alloy particles activated by one-step and two-step methods has been conducted from both a chemical and a morphological point of view. The combination of x-ray photoelectron spectroscopy (XPS) measurements and atomic force microscopy (AFM) imaging has allowed detection of the distribution of the formed compounds and depth quantification and estimation of the surface topographic parameters. For the two-step method, at the sensitization of the early stages, it is observed by AFM that Sn is absorbed in form of clusters that tend to completely cover the surface and form a continuous film. XPS analysis have shown that Sn and Pd are first absorbed in form of oxide (SnO{sub 2} and PdO) and hydroxide [Sn(OH){sub 4}]. After the entire sensitization step, the NiTi substrate is covered with Sn-based compounds. After the sensitization and the activation steps the powder roughness increases. Behavior of the Sn and Pd growth for the one-step method does not follow the behavior found for the two-step method. Indeed, XPS analysis shows a three-dimensional (3D) growth of Pd clusters on top of a mixture of metallic tin, oxide (SnO) and hydroxide [Sn(OH){sub 2}]. These Pd clusters are covered with a thin layer of Pd-oxide contamination induced by the electroless process. The mean roughness for the one-step and two-step processes are equivalent. After copper deposition, the decrease of mean roughness is attributed to a filling of surface valleys, observed after the Sn-Pd coating step.

  6. In Situ Adsorption Studies at the Solid/Liquid Interface:Characterization of Biological Surfaces and Interfaces Using SumFrequency Generation Vibrational Spectroscopy, Atomic Force Microscopy,and Quartz Crystal Microbalance

    SciTech Connect (OSTI)

    Phillips, D.C.

    2006-05-16

    Sum frequency generation (SFG) vibrational spectroscopy, atomic force microscopy (AFM), and quartz crystal microbalance (QCM) have been used to study the molecular surface structure, surface topography and mechanical properties, and quantitative adsorbed amount of biological molecules at the solid-liquid interface. The molecular-level behavior of designed peptides adsorbed on hydrophobic polystyrene and hydrophilic silica substrates has been examined as a model of protein adsorption on polymeric biomaterial surfaces. Proteins are such large and complex molecules that it is difficult to identify the features in their structure that lead to adsorption and interaction with solid surfaces. Designed peptides which possess secondary structure provide simple model systems for understanding protein adsorption. Depending on the amino acid sequence of a peptide, different secondary structures ({alpha}-helix and {beta}-sheet) can be induced at apolar (air/liquid or air/solid) interfaces. Having a well-defined secondary structure allows experiments to be carried out under controlled conditions, where it is possible to investigate the affects of peptide amino acid sequence and chain length, concentration, buffering effects, etc. on adsorbed peptide structure. The experiments presented in this dissertation demonstrate that SFG vibrational spectroscopy can be used to directly probe the interaction of adsorbing biomolecules with a surface or interface. The use of well designed model systems aided in isolation of the SFG signal of the adsorbing species, and showed that surface functional groups of the substrate are sensitive to surface adsorbates. The complementary techniques of AFM and QCM allowed for deconvolution of the effects of surface topography and coverage from the observed SFG spectra. Initial studies of biologically relevant surfaces are also presented: SFG spectroscopy was used to study the surface composition of common soil bacteria for use in bioremediation of nuclear waste.

  7. Sensing Current and Forces with SPM

    SciTech Connect (OSTI)

    Park, Jeong Y.; Maier, Sabine; Hendriksen, Bas; Salmeron, Miquel

    2010-07-02

    Atomic force microscopy (AFM) and scanning tunneling microscopy (STM) are well established techniques to image surfaces and to probe material properties at the atomic and molecular scale. In this review, we show hybrid combinations of AFM and STM that bring together the best of two worlds: the simultaneous detection of atomic scale forces and conduction properties. We illustrate with several examples how the detection of forces during STM and the detection of currents during AFM can give valuable additional information of the nanoscale material properties.

  8. Long working distance interference microscope

    DOE Patents [OSTI]

    Sinclair, Michael B.; DeBoer, Maarten P.; Smith, Norman F.

    2004-04-13

    Disclosed is a long working distance interference microscope suitable for three-dimensional imaging and metrology of MEMS devices and test structures on a standard microelectronics probe station. The long working distance of 10-30 mm allows standard probes or probe cards to be used. This enables nanometer-scale 3-D height profiles of MEMS test structures to be acquired across an entire wafer. A well-matched pair of reference/sample objectives is not required, significantly reducing the cost of this microscope, as compared to a Linnik microinterferometer.

  9. Instead of splitting the atom --the

    E-Print Network [OSTI]

    Instead of splitting the atom - - the principle behind the 1940s Manhattan Project that build infinite. Instead of splitting the atom -- the principle behind the 1940s Manhattan Project that build gravitational forces ram hydrogen atoms together to produce helium, with solar energy the byproduct. On Earth

  10. Polymer Filler Aging and Failure Studied by Lateral Force Microscopy

    SciTech Connect (OSTI)

    Ratto, T; Saab, A P

    2009-05-27

    In the present work, we study, via force microscopy, the basic physical interactions of a single bead of silica filler with a PDMS matrix both before and after exposure to gamma radiation. Our goal was to confirm our results from last year, and to explore force microscopy as a means of obtaining particle-scale polymer/filler interactions suitable for use as empirical inputs to a computational model consisting of an ensemble of silica beads embedded in a PDMS matrix. Through careful calibration of a conventional atomic force microscope, we obtained both normal and lateral force data that was fitted to yield adhesion, surface shear modulus, and friction of a 1 {micro}m silica bead in contact with PDMS layers of various thickness. Comparison of these terms before and after gamma exposure indicated that initially, radiation exposure lead to softening of the PDMS, but eventually resulted in stiffening. Simultaneously, adhesion between the polymer and silica decreased. This could indicate a serious failure path for filled PDMS exposed to radiation, whereby stiffening of the bulk polymer leads to loss of compressive elastic behavior, while a decrease in polymer filler adhesion results in an increased likelihood of stress failure under load. In addition to further testing of radiation damaged polymers, we also performed FEA modeling of silica beads in a silicone matrix using the shear modulus and adhesion values isolated from the force microscopy experiments as model inputs. The resulting simulation indicated that as a polymer stiffens due to impinging radiation, it also undergoes weakening of adhesion to the filler. The implication is that radiation induces a compound failure mode in filled polymer systems.

  11. Protective Force

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2005-08-26

    Establishes requirements for management and operation of the DOE Protective Force (PF), establishes requirements for firearms operations and defines the firearms courses of fire. Cancels: DOE M 473.2-1A DOE M 473.2-2

  12. Protective Force

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2006-03-07

    The manual establishes requirements for management and operation of the DOE Protective Force, establishes requirements for firearms operations and defines the firearms courses of fire. Chg 1 dated 3/7/06. DOE M 470.4-3A cancels DOE M 470.4-3, Chg 1, Protective Force, dated 3-7-06, Attachment 2, Contractor Requirement Document (CRD) only (except for Section C). Chg 1, dated 3-7-06, cancels DOE M 470.4-3

  13. Optical modeling of Fresnel zoneplate microscopes

    E-Print Network [OSTI]

    Naulleau, Patrick

    2012-01-01

    of 12 nm Resolution Fresnel Zone Plate Lens based Soft X-rayOptical modeling of Fresnel zoneplate microscopes Patrick P.the development of Fresnel zoneplate based microscopes.

  14. A versatile LabVIEW and field-programmable gate array-based scanning probe microscope for in operando electronic device characterization

    SciTech Connect (OSTI)

    Berger, Andrew J. Page, Michael R.; Young, Justin R.; Bhallamudi, Vidya P.; Johnston-Halperin, Ezekiel; Pelekhov, Denis V.; Hammel, P. Chris; Jacob, Jan; Lewis, Jim; Wenzel, Lothar

    2014-12-15

    Understanding the complex properties of electronic and spintronic devices at the micro- and nano-scale is a topic of intense current interest as it becomes increasingly important for scientific progress and technological applications. In operando characterization of such devices by scanning probe techniques is particularly well-suited for the microscopic study of these properties. We have developed a scanning probe microscope (SPM) which is capable of both standard force imaging (atomic, magnetic, electrostatic) and simultaneous electrical transport measurements. We utilize flexible and inexpensive FPGA (field-programmable gate array) hardware and a custom software framework developed in National Instrument's LabVIEW environment to perform the various aspects of microscope operation and device measurement. The FPGA-based approach enables sensitive, real-time cantilever frequency-shift detection. Using this system, we demonstrate electrostatic force microscopy of an electrically biased graphene field-effect transistor device. The combination of SPM and electrical transport also enables imaging of the transport response to a localized perturbation provided by the scanned cantilever tip. Facilitated by the broad presence of LabVIEW in the experimental sciences and the openness of our software solution, our system permits a wide variety of combined scanning and transport measurements by providing standardized interfaces and flexible access to all aspects of a measurement (input and output signals, and processed data). Our system also enables precise control of timing (synchronization of scanning and transport operations) and implementation of sophisticated feedback protocols, and thus should be broadly interesting and useful to practitioners in the field.

  15. Investigation on dielectric properties of atomic layer deposited Al{sub 2}O{sub 3} dielectric films

    SciTech Connect (OSTI)

    Y?ld?z, Dilber Esra; Y?ld?r?m, Mert; Gökçen, Muharrem

    2014-05-15

    Al/Al{sub 2}O{sub 3}/p-Si Schottky barrier diodes (SBDs) were fabricated using atomic layer deposition technique in order to investigate dielectric properties of SBDs. For this purpose, admittance measurements were conducted at room temperature between ?1?V and 3?V in the frequency range of 10 kHz and 1?MHz. In addition to the investigation of Al{sub 2}O{sub 3} morphology using atomic force microscope, dielectric parameters; such as dielectric constant (??), dielectric loss (??), dielectric loss tangent (tan??), and real and imaginary parts of dielectric modulus (M? and M?, respectively), were calculated and effect of frequency on these parameters of Al/Al{sub 2}O{sub 3}/p-Si SBDs was discussed. Variations in these parameters at low frequencies were associated with the effect of interface states in low frequency region. Besides dielectric parameters, ac electrical conductivity of these SBDs was also investigated.

  16. Nuclear forces from chiral EFT: The unfinished business

    E-Print Network [OSTI]

    R. Machleidt; D. R. Entem

    2010-01-06

    In spite of the great progress we have seen in recent years in the derivation of nuclear forces from chiral effective field theory (EFT), some important issues are still unresolved. In this contribution, we discuss the open problems which have particular relevance for microscopic nuclear structure, namely, the proper renormalization of chiral nuclear potentials and sub-leading many-body forces.

  17. Four-probe measurements with a three-probe scanning tunneling microscope

    SciTech Connect (OSTI)

    Salomons, Mark [National Institute for Nanotechnology, National Research Council of Canada, Edmonton, Alberta T6G 2M9 (Canada)] [National Institute for Nanotechnology, National Research Council of Canada, Edmonton, Alberta T6G 2M9 (Canada); Martins, Bruno V. C.; Zikovsky, Janik; Wolkow, Robert A., E-mail: rwolkow@ualberta.ca [National Institute for Nanotechnology, National Research Council of Canada, Edmonton, Alberta T6G 2M9 (Canada); Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1 (Canada)

    2014-04-15

    We present an ultrahigh vacuum (UHV) three-probe scanning tunneling microscope in which each probe is capable of atomic resolution. A UHV JEOL scanning electron microscope aids in the placement of the probes on the sample. The machine also has a field ion microscope to clean, atomically image, and shape the probe tips. The machine uses bare conductive samples and tips with a homebuilt set of pliers for heating and loading. Automated feedback controlled tip-surface contacts allow for electrical stability and reproducibility while also greatly reducing tip and surface damage due to contact formation. The ability to register inter-tip position by imaging of a single surface feature by multiple tips is demonstrated. Four-probe material characterization is achieved by deploying two tips as fixed current probes and the third tip as a movable voltage probe.

  18. Gain narrowing in few-atom systems

    E-Print Network [OSTI]

    Tom Savels; Allard P. Mosk; Ad Lagendijk

    2006-05-31

    Using a density matrix approach, we study the simplest systems that display both gain and feedback: clusters of 2 to 5 atoms, one of which is pumped. The other atoms supply feedback through multiple scattering of light. We show that, if the atoms are in each other's near-field, the system exhibits large gain narrowing and spectral mode redistribution. The observed phenomena are more pronounced if the feedback is enhanced. Our system is to our knowledge the simplest exactly solvable microscopic system which shows the approach to laser oscillation.

  19. Scanning evanescent electro-magnetic microscope

    DOE Patents [OSTI]

    Xiang, Xiao-Dong (Alameda, CA); Gao, Chen (Anhui, CN); Schultz, Peter G. (La Jolla, CA); Wei, Tao (Sunnyvale, CA)

    2003-01-01

    A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.

  20. Scanning evanescent electro-magnetic microscope

    DOE Patents [OSTI]

    Xiang, Xiao-Dong (Alameda, CA); Gao, Chen (Alameda, CA)

    2001-01-01

    A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.

  1. Theoretical Framework for Microscopic Osmotic Phenomena Theoretical Framework for Microscopic Osmotic Phenomena

    E-Print Network [OSTI]

    Kramer, Peter

    Theoretical Framework for Microscopic Osmotic Phenomena Theoretical Framework for Microscopic Osmotic Phenomena Paul J. Atzberger Department of Mathematics University of California, Santa Barbara 25, 2007) The basic ingredients of osmotic pressure are a solvent fluid with a soluble molecular

  2. Co-localised Raman and force spectroscopy reveal the roles of hydrogen bonds and ?-? interactions in defining the mechanical properties of diphenylalanine nano- and micro-tubes

    SciTech Connect (OSTI)

    Sinjab, Faris; Bondakov, Georgi; Notingher, Ioan, E-mail: ioan.notingher@nottingham.ac.uk [School of Physics and Astronomy, University of Nottingham, Nottingham (United Kingdom)

    2014-06-23

    An integrated atomic force and polarized Raman microscope were used to measure the elastic properties of individual diphenylalanine (FF) nano- and micro-tubes and to obtain quantitative information regarding the inter-molecular interactions that define their mechanical properties. For individual tubes, co-localised force spectroscopy and Raman spectroscopy measurements allowed the calculation of the Young's and shear moduli (25?±?5?GPa and 0.28?±?0.05?GPa, respectively) and the contribution of hydrogen bonding network to the Young's modulus (?17.6?GPa). The ?-? interactions between the phenyl rings, dominated by T-type arrangements, were estimated based on previously published X-ray data to only 0.20?GPa. These results provide experimental evidence obtained from individual FF tubes that the network of H-bonds dominates the elastic properties of the FF tubes.

  3. If Only We Could Account For Every Atom (LBNL Summer Lecture Series)

    ScienceCinema (OSTI)

    Kisielowski, Christian

    2014-05-06

    Christian Kisielowski, an expert in electron microscopy at Lawrence Berkeley National Laboratory, investigates ways to allow studies of single atoms using sophisticated microscopes and imaginative techniques. His goal is to account for every atom in the interior of both simple and complex materials. Find out how he and his colleagues are breaking the barriers to account for every atom.

  4. Global Focus Microscope The Global Health Challenge

    E-Print Network [OSTI]

    . To address this need, we developed the Global Focus Microscope (GFM): a portable, battery- powered, inverted digi- tal images, the Global Focus Microscope comes with shelf for an iPhone 4. Figure 1. From left to right: Malaria parasites imaged at 1000x in bright field mode, tuberculosis imaged at 400x in bright

  5. Robotic CCD microscope for enhanced crystal recognition

    DOE Patents [OSTI]

    Segelke, Brent W. (San Ramon, CA); Toppani, Dominique (Livermore, CA)

    2007-11-06

    A robotic CCD microscope and procedures to automate crystal recognition. The robotic CCD microscope and procedures enables more accurate crystal recognition, leading to fewer false negative and fewer false positives, and enable detection of smaller crystals compared to other methods available today.

  6. Atom Interferometry

    ScienceCinema (OSTI)

    Mark Kasevich

    2010-01-08

    Atom de Broglie wave interferometry has emerged as a tool capable of addressing a diverse set of questions in gravitational and condensed matter physics, and as an enabling technology for advanced sensors in geodesy and navigation. This talk will review basic principles, then discuss recent applications and future directions. Scientific applications to be discussed include measurement of G (Newton?s constant), tests of the Equivalence Principle and post-Newtonian gravity, and study of the Kosterlitz-Thouless phase transition in layered superfluids. Technology applications include development of precision gryoscopes and gravity gradiometers. The talk will conclude with speculative remarks looking to the future: Can atom interference methods be sued to detect gravity waves? Can non-classical (entangled/squeezed state) atom sources lead to meaningful sensor performance improvements?

  7. Note: Long-range scanning tunneling microscope for the study of nanostructures on insulating substrates

    SciTech Connect (OSTI)

    Molina-Mendoza, Aday J.; Rodrigo, José G.; Rubio-Bollinger, Gabino; Island, Joshua; Burzuri, Enrique; Zant, Herre S. J. van der; Agraït, Nicolás; Condensed Matter Physics Center and Instituto Universitario de Ciencia de Materiales “Nicolás Cabrera,” Universidad Autónoma de Madrid, Campus de Cantoblanco, E-28049 Madrid; Instituto Madrileño de Estudios Avanzados en Nanociencia IMDEA-Nanociencia, E-28049 Madrid

    2014-02-15

    The scanning tunneling microscope (STM) is a powerful tool for studying the electronic properties at the atomic level, however, it is of relatively small scanning range and the fact that it can only operate on conducting samples prevents its application to study heterogeneous samples consisting of conducting and insulating regions. Here we present a long-range scanning tunneling microscope capable of detecting conducting micro and nanostructures on insulating substrates using a technique based on the capacitance between the tip and the sample and performing STM studies.

  8. Metallic adhesion and tunnelling at the atomic A Schirmeisen1

    E-Print Network [OSTI]

    Grütter, Peter

    Metallic adhesion and tunnelling at the atomic scale A Schirmeisen1 , G Cross1 , A Stalder1 , P Gr scaling parameter of = 0.2 nm. We conclude that not only the apex atoms contribute to the adhesion forces are discussed. The study of metallic adhesion on the atomic scale lays the foundation for the understanding

  9. WETTABILITY AND IMBIBITION: MICROSCOPIC DISTRIBUTION OF WETTING AND ITS CONSEQUENCES AT THE CORE AND FIELD SCALES

    SciTech Connect (OSTI)

    Jill S. Buckley; Norman R. Morrow; Chris Palmer; Purnendu K. Dasgupta

    2003-02-01

    The questions of reservoir wettability have been approached in this project from three directions. First, we have studied the properties of crude oils that contribute to wetting alteration in a reservoir. A database of more than 150 different crude oil samples has been established to facilitate examination of the relationships between crude oil chemical and physical properties and their influence on reservoir wetting. In the course of this work an improved SARA analysis technique was developed and major advances were made in understanding asphaltene stability including development of a thermodynamic Asphaltene Solubility Model (ASM) and empirical methods for predicting the onset of instability. The CO-Wet database is a resource that will be used to guide wettability research in the future. The second approach is to study crude oil/brine/rock interactions on smooth surfaces. Contact angle measurements were made under controlled conditions on mica surfaces that had been exposed to many of the oils in the CO-Wet database. With this wealth of data, statistical tests can now be used to examine the relationships between crude oil properties and the tendencies of those oils to alter wetting. Traditionally, contact angles have been used as the primary wetting assessment tool on smooth surfaces. A new technique has been developed using an atomic forces microscope that adds a new dimension to the ability to characterize oil-treated surfaces. Ultimately we aim to understand wetting in porous media, the focus of the third approach taken in this project. Using oils from the CO-Wet database, experimental advances have been made in scaling the rate of imbibition, a sensitive measure of core wetting. Application of the scaling group to mixed-wet systems has been demonstrated for a range of core conditions. Investigations of imbibition in gas/liquid systems provided the motivation for theoretical advances as well. As a result of this project we have many new tools for studying wetting at microscopic and macroscopic scales and a library of well-characterized fluids for use in studies of crude oil/brine/rock interactions.

  10. Classical and Quantum Chaos in Atom Optics

    E-Print Network [OSTI]

    Farhan Saif

    2006-04-10

    The interaction of an atom with an electromagnetic field is discussed in the presence of a time periodic external modulating force. It is explained that a control on atom by electromagnetic fields helps to design the quantum analog of classical optical systems. In these atom optical systems chaos may appear at the onset of external fields. The classical and quantum chaotic dynamics is discussed, in particular in an atom optics Fermi accelerator. It is found that the quantum dynamics exhibits dynamical localization and quantum recurrences.

  11. Kelvin Probe Force Microscopy for in situ Electrical Characterization of Organic Solar Cells

    E-Print Network [OSTI]

    Fisher, Frank

    Kelvin Probe Force Microscopy for in situ Electrical Characterization of Organic Solar Cells., University of Pittsburgh The most efficient organic solar cell today is made from blending conjugated donors and acceptors in bulk heterojunction organic solar cells. Most microscopic characterization

  12. Scanning Electron Microscopes in Materials Characterization ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scanning Electron Microscopes in Materials Characterization Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in...

  13. The classical mechanics of autonomous microscopic engines

    E-Print Network [OSTI]

    Lukas Gilz; Eike P. Thesing; James R. Anglin

    2015-09-08

    Even microscopic engines have hitherto been defined to require macroscopic elements such as heat reservoirs, but here we observe that what makes engines useful is energy transfer across a large ratio of dynamical time scales ("downconversion"), and that small, closed dynamical systems which could perform steady downconversion ("Hamiltonian daemons") would fulfill the practical requirements of autonomous microscopic engines. We show that such daemons are possible, and obey mechanical constraints comparable to, but different from, the laws of thermodynamics.

  14. Atomic rivals

    SciTech Connect (OSTI)

    Goldschmidt, B.

    1990-01-01

    This book is a memoir of rivalries among the Allies over the bomb, by a participant and observer. Nuclear proliferation began in the uneasy wartime collaboration of the United States, England, Canada, and Free France to produce the atom bomb. Through the changes of history, a young French chemist had a role in almost every act of this international drama. This memoir is based on Goldschmidt's own recollections, interviews with other leading figures, and 3,000 pages of newly declassified documents in Allied archives. From his own start as Marie Curie's lab assistant, Goldschmidt's career was closely intertwined with Frances complicated rise to membership in the nuclear club. As a refugee from the Nazis, he became part of the wartime nuclear energy project in Canada and found himself the only French scientist to work (although briefly) on the American atom bomb project.

  15. Highly charged ion based time of flight emission microscope

    DOE Patents [OSTI]

    Barnes, Alan V. (Livermore, CA); Schenkel, Thomas (San Francisco, CA); Hamza, Alex V. (Livermore, CA); Schneider, Dieter H. (Livermore, CA); Doyle, Barney (Albuquerque, NM)

    2001-01-01

    A highly charged ion based time-of-flight emission microscope has been designed, which improves the surface sensitivity of static SIMS measurements because of the higher ionization probability of highly charged ions. Slow, highly charged ions are produced in an electron beam ion trap and are directed to the sample surface. The sputtered secondary ions and electrons pass through a specially designed objective lens to a microchannel plate detector. This new instrument permits high surface sensitivity (10.sup.10 atoms/cm.sup.2), high spatial resolution (100 nm), and chemical structural information due to the high molecular ion yields. The high secondary ion yield permits coincidence counting, which can be used to enhance determination of chemical and topological structure and to correlate specific molecular species.

  16. X-ray laser microscope apparatus

    DOE Patents [OSTI]

    Suckewer, Szymon (Princeton, NJ); DiCicco, Darrell S. (Plainsboro, NJ); Hirschberg, Joseph G. (Coral Gables, FL); Meixler, Lewis D. (East Windsor, NJ); Sathre, Robert (Princeton, NJ); Skinner, Charles H. (Lawrenceville, NJ)

    1990-01-01

    A microscope consisting of an x-ray contact microscope and an optical microscope. The optical, phase contrast, microscope is used to align a target with respect to a source of soft x-rays. The source of soft x-rays preferably comprises an x-ray laser but could comprise a synchrotron or other pulse source of x-rays. Transparent resist material is used to support the target. The optical microscope is located on the opposite side of the transparent resist material from the target and is employed to align the target with respect to the anticipated soft x-ray laser beam. After alignment with the use of the optical microscope, the target is exposed to the soft x-ray laser beam. The x-ray sensitive transparent resist material whose chemical bonds are altered by the x-ray beam passing through the target mater GOVERNMENT LICENSE RIGHTS This invention was made with government support under Contract No. De-FG02-86ER13609 awarded by the Department of Energy. The Government has certain rights in this invention.

  17. Fragment Yields Calculated in a Time-Dependent Microscopic Theory...

    Office of Scientific and Technical Information (OSTI)

    Fragment Yields Calculated in a Time-Dependent Microscopic Theory of Fission Citation Details In-Document Search Title: Fragment Yields Calculated in a Time-Dependent Microscopic...

  18. Microscopic theory of quantum anomalous Hall effect in graphene...

    Office of Scientific and Technical Information (OSTI)

    Microscopic theory of quantum anomalous Hall effect in graphene Prev Next Title: Microscopic theory of quantum anomalous Hall effect in graphene Authors: Qiao, Zhenhua ;...

  19. Toward Understanding the Microscopic Origin of Nuclear Clustering...

    Office of Scientific and Technical Information (OSTI)

    Toward Understanding the Microscopic Origin of Nuclear Clustering Citation Details In-Document Search Title: Toward Understanding the Microscopic Origin of Nuclear Clustering Open...

  20. Measuring Atomic Properties with an Atom Interferometer

    E-Print Network [OSTI]

    Roberts, Tony David

    2006-06-28

    Two experiments are presented which measure atomic properties using an atom interferometer. The interferometer splits the sodium de Broglie wave into two paths,

  1. Piezoresistive cantilever force-clamp system

    SciTech Connect (OSTI)

    Park, Sung-Jin; Petzold, Bryan C.; Pruitt, Beth L. [Department of Mechanical Engineering, Stanford University, Stanford, California 94305 (United States); Goodman, Miriam B. [Department of Molecular and Cellular Physiology, Stanford University, Stanford, California 94305 (United States)

    2011-04-15

    We present a microelectromechanical device-based tool, namely, a force-clamp system that sets or ''clamps'' the scaled force and can apply designed loading profiles (e.g., constant, sinusoidal) of a desired magnitude. The system implements a piezoresistive cantilever as a force sensor and the built-in capacitive sensor of a piezoelectric actuator as a displacement sensor, such that sample indentation depth can be directly calculated from the force and displacement signals. A programmable real-time controller operating at 100 kHz feedback calculates the driving voltage of the actuator. The system has two distinct modes: a force-clamp mode that controls the force applied to a sample and a displacement-clamp mode that controls the moving distance of the actuator. We demonstrate that the system has a large dynamic range (sub-nN up to tens of {mu}N force and nm up to tens of {mu}m displacement) in both air and water, and excellent dynamic response (fast response time, <2 ms and large bandwidth, 1 Hz up to 1 kHz). In addition, the system has been specifically designed to be integrated with other instruments such as a microscope with patch-clamp electronics. We demonstrate the capabilities of the system by using it to calibrate the stiffness and sensitivity of an electrostatic actuator and to measure the mechanics of a living, freely moving Caenorhabditis elegans nematode.

  2. Nuclear symmetry energy and the role of the tensor force

    E-Print Network [OSTI]

    Isaac Vidana; Artur Polls; Constanca Providencia

    2011-07-27

    Using the Hellmann--Feynman theorem we analyze the contribution of the different terms of the nucleon-nucleon interaction to the nuclear symmetry energy $E_{sym}$ and the slope parameter $L$. The analysis is performed within the microscopic Brueckner--Hartree--Fock approach using the Argonne V18 potential plus the Urbana IX three-body force. We find that the main contribution to $E_{sym}$ and $L$ is due to the tensor component of the nuclear force.

  3. Design of a new reactor-like high temperature near ambient pressure scanning tunneling microscope for catalysis studies

    E-Print Network [OSTI]

    Tao, Franklin Feng; Nguyen, Luan; Zhang, Shiran

    2013-01-01

    Here, we present the design of a new reactor-like high-temperature near ambient pressure scanning tunneling microscope (HT-NAP-STM) for catalysis studies. This HT-NAP-STM was designed for exploration of structures of catalyst surfaces at atomic...

  4. Atomic Structures

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O DBiomass and BiofuelsPhysicist47JulyInnovationAtomic Layer

  5. Miniature self-contained vacuum compatible electronic imaging microscope

    DOE Patents [OSTI]

    Naulleau, Patrick P. (Oakland, CA); Batson, Phillip J. (Alameda, CA); Denham, Paul E. (Crockett, CA); Jones, Michael S. (San Francisco, CA)

    2001-01-01

    A vacuum compatible CCD-based microscopic camera with an integrated illuminator. The camera can provide video or still feed from the microscope contained within a vacuum chamber. Activation of an optional integral illuminator can provide light to illuminate the microscope subject. The microscope camera comprises a housing with a objective port, modified objective, beam-splitter, CCD camera, and LED illuminator.

  6. Microscopic calculations of the characteristics of radiative nuclear reactions for double-magic nuclei

    E-Print Network [OSTI]

    Oleg Achakovskiy; Sergei Kamerdzhiev; Victor Tselyaev; Mikhail Shitov

    2015-11-03

    The neutron capture cross sections and average radiative widths of neutron resonances for two double-magic nuclei 132Sn and 208Pb have been calculated using the microscopic photon strength functions, which were obtained within the microscopic self-consistent version of the extended theory of finite Fermi systems in the time blocking approximation. For the first time, the microscopic PSFs have been obtained within the fully self-consistent approach with exact accounting for the single particle continuum (for 208Pb). The approach includes phonon coupling effects in addition to the standard RPA approach. The known Skyrme force has been used. The calculations of nuclear reaction characteristics have been performed with the EMPIRE 3.1 nuclear reaction code. Here, three nuclear level density (NLD) models have been used: the so-called phenomenological GSM, the EMPIRE specific (or Enhanced GSM) and the microscopical combinatorial HFB NLD models. For both considered characteristics we found a significant disagreement between the results obtained with the GSM and HFB NLD models. For 208Pb, a reasonable agreement has been found with systematics for the average radiative widths values with HFB NLD and with the experimental data for the HFB NLD average resonance spacing D0, while for these two quantities the differences between the values obtained with GSM and HFB NLD are of several orders of magnitude. The discrepancies between the results with the phenomenological EGLO PSF and microscopic RPA or TBA are much less for the same NLD model.

  7. Atomic magnetometer

    DOE Patents [OSTI]

    Schwindt, Peter (Albuquerque, NM); Johnson, Cort N. (Albuquerque, NM)

    2012-07-03

    An atomic magnetometer is disclosed which uses a pump light beam at a D1 or D2 transition of an alkali metal vapor to magnetically polarize the vapor in a heated cell, and a probe light beam at a different D2 or D1 transition to sense the magnetic field via a polarization rotation of the probe light beam. The pump and probe light beams are both directed along substantially the same optical path through an optical waveplate and through the heated cell to an optical filter which blocks the pump light beam while transmitting the probe light beam to one or more photodetectors which generate electrical signals to sense the magnetic field. The optical waveplate functions as a quarter waveplate to circularly polarize the pump light beam, and as a half waveplate to maintain the probe light beam linearly polarized.

  8. The Characteristics of the Factors That Govern the Preferred Force in the Social Force Model of Pedestrian Movement

    E-Print Network [OSTI]

    Shuaib, Mohammed Mahmod; Abu-Sulyman, Ibtesam M

    2010-01-01

    The social force model which belongs to the microscopic pedestrian studies has been considered as the supremacy by many researchers and due to the main feature of reproducing the self-organized phenomena resulted from pedestrian dynamic. The Preferred Force which is a measurement of pedestrian's motivation to adapt his actual velocity to his desired velocity is an essential term on which the model was set up. This Force has gone through stages of development: first of all, Helbing and Molnar (1995) have modeled the original force for the normal situation. Second, Helbing and his co-workers (2000) have incorporated the panic situation into this force by incorporating the panic parameter to account for the panic situations. Third, Lakoba and Kaup (2005) have provided the pedestrians some kind of intelligence by incorporating aspects of the decision-making capability. In this paper, the authors analyze the most important incorporations into the model regarding the preferred force. They make comparisons between t...

  9. Method for imaging liquid and dielectric materials with scanning polarization force microscopy

    DOE Patents [OSTI]

    Hu, Jun (Berkeley, CA); Ogletree, D. Frank (El Cerrito, CA); Salmeron, Miguel (El Cerrito, CA); Xiao, Xudong (Kowloon, CN)

    1999-01-01

    The invention images dielectric polarization forces on surfaces induced by a charged scanning force microscope (SFM) probe tip. On insulators, the major contribution to the surface polarizability at low frequencies is from surface ions. The mobility of these ions depends strongly on the humidity. Using the inventive SFM, liquid films, droplets, and other weakly adsorbed materials have been imaged.

  10. SLAC All Access: X-ray Microscope

    ScienceCinema (OSTI)

    Nelson, Johanna; Liu, Yijin

    2014-06-13

    SLAC physicists Johanna Nelson and Yijin Liu give a brief overview of the X-ray microscope at the Stanford Synchrotron Radiation Lightsource (SSRL) that is helping improve rechargeable-battery technology by letting researchers peek into the inner workings of batteries as they operate.

  11. Superconducting qubit as a quantum transformer routing entanglement between a microscopic quantum memory and a macroscopic resonator

    SciTech Connect (OSTI)

    Kemp, Alexander; Saito, Shiro; Semba, Kouichi [NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya Atsugi-shi, Kanagawa 243-0198 (Japan); Munro, William J. [NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya Atsugi-shi, Kanagawa 243-0198 (Japan); National Institute of Informatics 2-1-2 Hitotsubashi, Chiyoda ku, Tokyo 101-8430 (Japan); Nemoto, Kae [National Institute of Informatics 2-1-2 Hitotsubashi, Chiyoda ku, Tokyo 101-8430 (Japan)

    2011-09-01

    We demonstrate experimentally the creation and measurement of an entangled state between a microscopic two-level system (TLS), formed by a defect in an oxide layer, and a macroscopic superconducting resonator, where their indirect interaction is mediated by an artificial atom, a superconducting persistent current qubit (PCQB). Under appropriate conditions, we found the coherence time of the TLS, the resonator, and the entangled state of these two are significantly longer than the Ramsey dephasing time of PCQB itself. This demonstrates that a PCQB can be used as a quantum transformer to address high coherence microscopic quantum memories by connecting them to macroscopic quantum buses.

  12. Magneto-optical cooling of atoms Mark G. Raizen,1,

    E-Print Network [OSTI]

    Raizen, Mark G.

    Magneto-optical cooling of atoms Mark G. Raizen,1, * Dmitry Budker,2,3 Simon M. Rochester,3 Julia propose an alternative method to laser cooling. Our approach utilizes the extreme brightness forces, can be used to cool the translational motion of atoms. This approach does not rely on momentum

  13. Revised Parameters for the AMOEBA Polarizable Atomic Multipole Water Model

    E-Print Network [OSTI]

    Ponder, Jay

    Revised Parameters for the AMOEBA Polarizable Atomic Multipole Water Model Marie L. Laury,, Lee for the AMOEBA polarizable atomic multipole water model is developed. An automated procedure, Force. With advances in computing power, calibration data, and optimization techniques, we recommend the use

  14. Scanning tunneling microscope assembly, reactor, and system

    DOE Patents [OSTI]

    Tao, Feng; Salmeron, Miquel; Somorjai, Gabor A

    2014-11-18

    An embodiment of a scanning tunneling microscope (STM) reactor includes a pressure vessel, an STM assembly, and three spring coupling objects. The pressure vessel includes a sealable port, an interior, and an exterior. An embodiment of an STM system includes a vacuum chamber, an STM reactor, and three springs. The three springs couple the STM reactor to the vacuum chamber and are operable to suspend the scanning tunneling microscope reactor within the interior of the vacuum chamber during operation of the STM reactor. An embodiment of an STM assembly includes a coarse displacement arrangement, a piezoelectric fine displacement scanning tube coupled to the coarse displacement arrangement, and a receiver. The piezoelectric fine displacement scanning tube is coupled to the coarse displacement arrangement. The receiver is coupled to the piezoelectric scanning tube and is operable to receive a tip holder, and the tip holder is operable to receive a tip.

  15. Protective Force Program Manual

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2000-06-30

    Provides detailed requirements to supplement DOE O 473.2, Protective Force Program, which establishes the requirements and responsibilities for management and operation of the Department of Energy (DOE) Protective Force (PF) Program. Does not cancel other directives.

  16. Castro with Carranzista Forces 

    E-Print Network [OSTI]

    Unknown

    2011-09-05

    Casimir pistons are models in which finite Casimir forces can be calculated without any suspect renormalizations. It has been suggested that such forces are always attractive, but we present several counterexamples, notably ...

  17. Fermionic Luttinger liquids from a microscopic perspective

    E-Print Network [OSTI]

    Manuel Valiente; Lawrence G. Phillips; Nikolaj T. Zinner; Patrik Ohberg

    2015-05-13

    We consider interacting one-dimensional, spinless Fermi gases, whose low-energy properties are described by Luttinger liquid theory. We perform a systematic, in-depth analysis of the relation between the macroscopic, phenomenological parameters of Luttinger liquid effective field theory, and the microscopic interactions of the Fermi gas. In particular, we begin by explaining how to model effective interactions in one dimension, which we then apply to the main forward scattering channel -- the interbranch collisions -- common to these systems. We renormalise the corresponding interbranch phenomenological constants in favour of scattering phase shifts. Interestingly, our renormalisation procedure shows (i) how Luttinger's model arises in a completely natural way -- and not as a convenient approximation -- from Tomonaga's model, and (ii) the reasons behind the interbranch coupling constant remaining unrenormalised in Luttinger's model. We then consider the so-called intrabranch processes, whose phenomenological coupling constant is known to be fixed by charge conservation, but whose microscopic origin is not well understood. We show that, contrary to general belief and common sense, the intrabranch interactions appearing in Luttinger liquid theory do not correspond to an intrabranch scattering channel, nor an energy shift due to intrabranch interactions, in the microscopic theory. Instead, they are due to interbranch processes. We finally apply our results to a particular example of an exactly solvable model, namely the fermionic dual to the Lieb-Liniger model in the Tonks-Girardeau and super-Tonks-Girardeau regimes.

  18. 3D Printed Microscope for Mobile Devices that Cost Pennies

    ScienceCinema (OSTI)

    Erikson, Rebecca; Baird, Cheryl; Hutchinson, Janine

    2015-06-23

    Scientists at PNNL have designed a 3D-printable microscope for mobile devices using pennies worth of plastic and glass materials. The microscope has a wide range of uses, from education to in-the-field science.

  19. 3D Printed Microscope for Mobile Devices that Cost Pennies

    SciTech Connect (OSTI)

    Erikson, Rebecca; Baird, Cheryl; Hutchinson, Janine

    2014-09-15

    Scientists at PNNL have designed a 3D-printable microscope for mobile devices using pennies worth of plastic and glass materials. The microscope has a wide range of uses, from education to in-the-field science.

  20. Administering Work Force Discipline

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2015-05-14

    The order provides requirements and responsibilities for administering work force discipline and corrective actions. Supersedes DOE O 3750.1.

  1. Continuum-kinetic-microscopic model of lung clearance due to core-annular fluid entrainment

    SciTech Connect (OSTI)

    Mitran, Sorin

    2013-07-01

    The human lung is protected against aspirated infectious and toxic agents by a thin liquid layer lining the interior of the airways. This airway surface liquid is a bilayer composed of a viscoelastic mucus layer supported by a fluid film known as the periciliary liquid. The viscoelastic behavior of the mucus layer is principally due to long-chain polymers known as mucins. The airway surface liquid is cleared from the lung by ciliary transport, surface tension gradients, and airflow shear forces. This work presents a multiscale model of the effect of airflow shear forces, as exerted by tidal breathing and cough, upon clearance. The composition of the mucus layer is complex and variable in time. To avoid the restrictions imposed by adopting a viscoelastic flow model of limited validity, a multiscale computational model is introduced in which the continuum-level properties of the airway surface liquid are determined by microscopic simulation of long-chain polymers. A bridge between microscopic and continuum levels is constructed through a kinetic-level probability density function describing polymer chain configurations. The overall multiscale framework is especially suited to biological problems due to the flexibility afforded in specifying microscopic constituents, and examining the effects of various constituents upon overall mucus transport at the continuum scale.

  2. Optical gradient force nano-imaging and -spectroscopy

    E-Print Network [OSTI]

    Yang, Honghua U

    2015-01-01

    Nanoscale forces play an important role in different scanning probe microscopies, most notably atomic force microscopy (AFM). In contrast, in scanning near-field optical microscopy (SNOM) a light-induced coupled local optical polarization between tip and sample is typically detected by scattering to the far field. Measurements of the optical gradient force associated with that optical near-field excitation would offer a novel optical scanning probe modality. Here we provide a generalized theory of optical gradient force nano-imaging and -spectroscopy. We quantify magnitude and distance dependence of the optical gradient force and its spectral response. We show that the optical gradient force is dispersive for single particle electronic and vibrational resonances, distinct from recent claims of its experimental observation. In contrast, the force can be absorptive for collective resonances. We provide a guidance for its measurements and distinction from competing processes such as thermal expansion.

  3. Structure and Dynamics of Dinucleosomes Assessed by Atomic Force Microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Filenko, Nina A.; Palets, Dmytro B.; Lyubchenko, Yuri L.

    2012-01-01

    Dynamics of nucleosomes and their interactions are important for understanding the mechanism of chromatin assembly. Internucleosomal interaction is required for the formation of higher-order chromatin structures. Although H1 histone is critically involved in the process of chromatin assembly, direct internucleosomal interactions contribute to this process as well. To characterize the interactions of nucleosomes within the nucleosome array, we designed a dinucleosome and performed direct AFM imaging. The analysis of the AFM data showed dinucleosomes are very dynamic systems, enabling the nucleosomes to move in a broad range along the DNA template. Di-nucleosomes in close proximity were observed, but their populationmore »was low. The use of the zwitterionic detergent, CHAPS, increased the dynamic range of the di-nucleosome, facilitating the formation of tight di-nucleosomes. The role of CHAPS and similar natural products in chromatin structure and dynamics is also discussed.« less

  4. Customized atomic force microscopy probe by focused-ion-beam...

    Office of Scientific and Technical Information (OSTI)

    that tall (18 m) cantilever tips fabricated by this approach reduce squeeze-film damping, which fits predictions from hydrodynamic theory, and results in an increased...

  5. The study of organic crystals by atomic force microscopy

    E-Print Network [OSTI]

    Chow, Ernest Ho Hin

    2014-07-01

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 2.16 2-D and 3-D height images of a chocolate sample obtained at various storage times. . . . . . . . . . . . . . . . . . . . . . . . . 25 2.17 AFM images of the {110} face of paracetamol crystals. . . . . . 26 2.18 AFM images of glycine crystals... BFDH growth morphology of ASA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 3.4 AFM 3-D images of ASA (001) surface under dissolution. . . . . 42 3.5 AFM Deflection images of ASA (100) face etched by water, ace- tone, and ethyl...

  6. Force, current and field effects in single atom manipulation

    E-Print Network [OSTI]

    Braun, Kai-Felix

    ) surface at 5K. The interpretation of the feed-back loop signal gives a precise picture of the movement-induced diffusion was used to measure the influence of the electric field which can be ruled out at low biases the movement of the tip the feed-back loop signal is recorded. These tip-height or manipulation curves have

  7. Ultrasonic-Based Mode-Synthesizing Atomic Force Microscopy - Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal designUltrafast Transformations inmixtureboundaries

  8. Fast atomic transport without vibrational heating

    E-Print Network [OSTI]

    E. Torrontegui; S. Ibáñez; Xi Chen; A. Ruschhaupt; D. Guéry-Odelin; J. G. Muga

    2010-10-15

    We use the dynamical invariants associated with the Hamiltonian of an atom in a one dimensional moving trap to inverse engineer the trap motion and perform fast atomic transport without final vibrational heating. The atom is driven non-adiabatically through a shortcut to the result of adiabatic, slow trap motion. For harmonic potentials this only requires designing appropriate trap trajectories, whereas perfect transport in anharmonic traps may be achieved by applying an extra field to compensate the forces in the rest frame of the trap. The results can be extended to atom stopping or launching. The limitations due to geometrical constraints, energies and accelerations involved are analyzed, as well as the relation to previous approaches (based on classical trajectories or "fast-forward" and "bang-bang" methods) which can be integrated in the invariant-based framework.

  9. An ytterbium quantum gas microscope with narrow-line laser cooling

    E-Print Network [OSTI]

    Yamamoto, Ryuta; Kuno, Takuma; Kato, Kohei; Takahashi, Yoshiro

    2015-01-01

    We demonstrate site-resolved imaging of individual bosonic $^{174}\\mathrm{Yb}$ atoms in a Hubbard-regime two-dimensional optical lattice with a short lattice constant of 266 nm. To suppress the heating by probe light with the $^1S_0$-$^1P_1$ transition of the wavelength $\\lambda$ = 399 nm for high-resolution imaging and preserve atoms at the same lattice sites during the fluorescence imaging, we simultaneously cool atoms by additionally applying narrow-line optical molasses with the $^1S_0$-$^3P_1$ transition of the wavelength $\\lambda$ = 556 nm. We achieve a low temperature of $T = 7.4(1.3)\\ \\mu\\mathrm{K}$, corresponding to a mean oscillation quantum number along the horizontal axes of 0.22(4) during imaging process. We detect on average 200 fluorescence photons from a single atom within 400 ms exposure time, and estimate the detection fidelity of 87(2)%. The realization of a quantum gas microscope with enough fidelity for Yb atoms in a Hubbard-regime optical lattice opens up the possibilities for studying v...

  10. Braking system for use with an arbor of a microscope

    DOE Patents [OSTI]

    Norgren, Duane U. (Orinda, CA)

    1984-01-01

    A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling device causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.

  11. Microscopic Theory of Nuclear Fission: A Review

    E-Print Network [OSTI]

    N. Schunck; L. M. Robledo

    2015-11-24

    This article reviews how nuclear fission is described within nuclear density functional theory. In spontaneous fission, half-lives are the main observables and quantum tunnelling the essential concept, while in induced fission the focus is on fragment properties and explicitly time-dependent approaches are needed. The cornerstone of the current microscopic theory of fission is the energy density functional formalism. Its basic tenets, including tools such as the HFB theory, effective two-body effective nuclear potentials, finite-temperature extensions and beyond mean-field corrections, are presented succinctly. The EDF approach is often combined with the hypothesis that the time-scale of the large amplitude collective motion driving the system to fission is slow compared to typical time-scales of nucleons inside the nucleus. In practice, this hypothesis of adiabaticity is implemented by introducing (a few) collective variables and mapping out the many-body Schr\\"odinger equation into a collective Schr\\"odinger-like equation for the nuclear wave-packet. Scission configurations indicate where the split occurs. This collective Schr\\"odinger equation depends on an inertia tensor that includes the response of the system to small changes in the collective variables and also plays a special role in the determination of spontaneous fission half-lives. A trademark of the microscopic theory of fission is the tremendous amount of computing needed for practical applications. In particular, the successful implementation of the theories presented in this article requires a very precise numerical resolution of the HFB equations for large values of the collective variables. Finally, a selection of the most recent and representative results obtained for both spontaneous and induced fission is presented with the goal of emphasizing the coherence of the microscopic approaches employed.

  12. Calibration of an interfacial force microscope for MEMS metrology : FY08-09

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing Bacteria (TechnicalTransmission, Distributioncoupled-channels method(Conference)

  13. Calibration of an interfacial force microscope for MEMS metrology : FY08-09

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing Bacteria (TechnicalTransmission, Distributioncoupled-channels

  14. Aberration corrected 1.2-MV cold field-emission transmission electron microscope with a sub-50-pm resolution

    SciTech Connect (OSTI)

    Akashi, Tetsuya; Takahashi, Yoshio; Tanigaki, Toshiaki Shimakura, Tomokazu; Kawasaki, Takeshi; Furutsu, Tadao; Shinada, Hiroyuki; Osakabe, Nobuyuki; Müller, Heiko; Haider, Maximilian; Tonomura, Akira

    2015-02-16

    Atomic-resolution electromagnetic field observation is critical to the development of advanced materials and to the unveiling of their fundamental physics. For this purpose, a spherical-aberration corrected 1.2-MV cold field-emission transmission electron microscope has been developed. The microscope has the following superior properties: stabilized accelerating voltage, minimized electrical and mechanical fluctuation, and coherent electron emission. These properties have enabled to obtain 43-pm information transfer. On the bases of these performances, a 43-pm resolution has been obtained by correcting lens aberrations up to the third order. Observations of GaN [411] thin crystal showed a projected atomic locations with a separation of 44?pm.

  15. Ponderomotive phase plate for transmission electron microscopes

    DOE Patents [OSTI]

    Reed, Bryan W. (Livermore, CA)

    2012-07-10

    A ponderomotive phase plate system and method for controllably producing highly tunable phase contrast transfer functions in a transmission electron microscope (TEM) for high resolution and biological phase contrast imaging. The system and method includes a laser source and a beam transport system to produce a focused laser crossover as a phase plate, so that a ponderomotive potential of the focused laser crossover produces a scattering-angle-dependent phase shift in the electrons of the post-sample electron beam corresponding to a desired phase contrast transfer function.

  16. Acoustic microscope surface inspection system and method

    DOE Patents [OSTI]

    Khuri-Yakub, Butrus T. (Palo Alto, CA); Parent, Philippe (Chilly-Mazarin, FR); Reinholdtsen, Paul A. (Seattle, WA)

    1991-01-01

    An acoustic microscope surface inspection system and method in which pulses of high frequency electrical energy are applied to a transducer which forms and focuses acoustic energy onto a selected location on the surface of an object and receives energy from the location and generates electrical pulses. The phase of the high frequency electrical signal pulses are stepped with respected to the phase of a reference signal at said location. An output signal is generated which is indicative of the surface of said selected location. The object is scanned to provide output signals representative of the surface at a plurality of surface locations.

  17. Scanning tip microwave near field microscope

    DOE Patents [OSTI]

    Xiang, Xiao-Dong (Alameda, CA); Schultz, Peter G. (Oakland, CA); Wei, Tao (Albany, CA)

    1998-01-01

    A microwave near field microscope has a novel microwave probe structure wherein the probing field of evanescent radiation is emitted from a sharpened metal tip instead of an aperture or gap. This sharpened tip, which is electrically and mechanically connected to a central electrode, extends through and beyond an aperture in an endwall of a microwave resonating device such as a microwave cavity resonator or a microwave stripline resonator. Since the field intensity at the tip increases as the tip sharpens, the total energy which is radiated from the tip and absorbed by the sample increases as the tip sharpens. The result is improved spatial resolution without sacrificing sensitivity.

  18. Acoustic microscope surface inspection system and method

    DOE Patents [OSTI]

    Khuri-Yakub, B.T.; Parent, P.; Reinholdtsen, P.A.

    1991-02-26

    An acoustic microscope surface inspection system and method are described in which pulses of high frequency electrical energy are applied to a transducer which forms and focuses acoustic energy onto a selected location on the surface of an object and receives energy from the location and generates electrical pulses. The phase of the high frequency electrical signal pulses are stepped with respect to the phase of a reference signal at said location. An output signal is generated which is indicative of the surface of said selected location. The object is scanned to provide output signals representative of the surface at a plurality of surface locations. 7 figures.

  19. Microscopic Models of Heavy Ion Interactions

    E-Print Network [OSTI]

    Capella, A

    2003-01-01

    An introduction to dynamical microscopic models of hadronic and nuclear interactions is presented. Special emphasis is put in the relation between multiparticle production and total cross-section contributions. In heavy ion collisions, some observables, considered as signals of the production of a Quark Gluon Plasma (QGP), are studied. It is shown that they can only be described if final state interactions are introduced. It is argued that the cross-sections required are too small to drive the system to thermal equilibrium within the duration time of the final state interaction.

  20. A Microscopic Double-Slit Experiment

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach HomeA Better Anode Design to Improve Lithium-Ion Batteries Print Lithium-ionAA Microscopic Double-Slit

  1. A Microscopic Double-Slit Experiment

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach HomeA Better Anode Design to Improve Lithium-Ion Batteries Print Lithium-ionAA Microscopic Double-SlitA

  2. A Microscopic Double-Slit Experiment

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach HomeA Better Anode Design to Improve Lithium-Ion Batteries Print Lithium-ionAA Microscopic Double-SlitAA

  3. A Microscopic Double-Slit Experiment

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach HomeA Better Anode Design to Improve Lithium-Ion Batteries Print Lithium-ionAA Microscopic Double-SlitAAA

  4. A Microscopic Double-Slit Experiment

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach HomeA Better Anode Design to Improve Lithium-Ion Batteries Print Lithium-ionAA Microscopic

  5. Disorder-Induced Microscopic Magnetic Memory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalentLaboratory | National(Technical Report)Disorder-Induced Microscopic

  6. The Scanning Electron Microscope As An Accelerator For The Undergraduate Advanced Physics Laboratory

    SciTech Connect (OSTI)

    Peterson, Randolph S.; Berggren, Karl K.; Mondol, Mark

    2011-06-01

    Few universities or colleges have an accelerator for use with advanced physics laboratories, but many of these institutions have a scanning electron microscope (SEM) on site, often in the biology department. As an accelerator for the undergraduate, advanced physics laboratory, the SEM is an excellent substitute for an ion accelerator. Although there are no nuclear physics experiments that can be performed with a typical 30 kV SEM, there is an opportunity for experimental work on accelerator physics, atomic physics, electron-solid interactions, and the basics of modern e-beam lithography.

  7. The force on a body in active matter

    E-Print Network [OSTI]

    Wen Yan; John F. Brady

    2015-10-27

    We present a general theory for determining the force (and torque) exerted on a boundary (or body) in active matter. The theory extends the description of passive Brownian colloids to self-propelled active particles and applies for all ratios of the thermal energy $k_BT$ to the swimmer's activity $k_sT_s = \\zeta U_0^2\\tau_R/6$, where $\\zeta$ is the Stokes drag coefficient, $U_0$ is the swim speed and $\\tau_R$ is the reorientation time of the active particles. The theory has a natural microscopic length scale over which concentration and orientation distributions are confined near boundaries, but the microscopic length does not appear in the force. The swim pressure emerges naturally and dominates the behavior when the boundary size is large compared to the swimmer's run length $\\ell = U_0\\tau_R$. The theory is used to predict the motion of bodies of all sizes immersed in active matter.

  8. Dilution and resonance-enhanced repulsion in nonequilibrium fluctuation forces

    SciTech Connect (OSTI)

    Bimonte, Giuseppe [Dipartimento di Scienze Fisiche, Universita di Napoli Federico II, Complesso Universitario MSA, Via Cintia, I-80126 Napoli (Italy); INFN Sezione di Napoli, I-80126 Napoli (Italy); Emig, Thorsten [Laboratoire de Physique Theorique et Modeles Statistiques, CNRS UMR 8626, Bat. 100, Universite Paris-Sud, F-91405 Orsay cedex (France); Krueger, Matthias; Kardar, Mehran [Massachusetts Institute of Technology, Department of Physics, Cambridge, Massachusetts 02139 (United States)

    2011-10-15

    In equilibrium, forces induced by fluctuations of the electromagnetic field between electrically polarizable objects (microscopic or macroscopic) in vacuum are generically attractive. The force may, however, become repulsive for microscopic particles coupled to thermal baths with different temperatures. We demonstrate that this nonequilibrium repulsion can be realized also between macroscopic objects, as planar slabs, if they are kept at different temperatures. It is shown that repulsion can be enhanced by (i) tuning of material resonances in the thermal region and by (ii) reducing the dielectric contrast due to ''dilution''. This can lead to stable equilibrium positions. We discuss the realization of these effects for aerogels, yielding repulsion down to submicron distances at realistic porosities.

  9. Theoretical Framework for Microscopic Osmotic Phenomena

    E-Print Network [OSTI]

    P. J. Atzberger; P. R. Kramer

    2009-10-29

    The basic ingredients of osmotic pressure are a solvent fluid with a soluble molecular species which is restricted to a chamber by a boundary which is permeable to the solvent fluid but impermeable to the solute molecules. For macroscopic systems at equilibrium, the osmotic pressure is given by the classical van't Hoff Law, which states that the pressure is proportional to the product of the temperature and the difference of the solute concentrations inside and outside the chamber. For microscopic systems the diameter of the chamber may be comparable to the length-scale associated with the solute-wall interactions or solute molecular interactions. In each of these cases, the assumptions underlying the classical van't Hoff Law may no longer hold. In this paper we develop a general theoretical framework which captures corrections to the classical theory for the osmotic pressure under more general relationships between the size of the chamber and the interaction length scales. We also show that notions of osmotic pressure based on the hydrostatic pressure of the fluid and the mechanical pressure on the bounding walls of the chamber must be distinguished for microscopic systems. To demonstrate how the theoretical framework can be applied, numerical results are presented for the osmotic pressure associated with a polymer of N monomers confined in a spherical chamber as the bond strength is varied.

  10. Casimir force: an alternative treatment

    E-Print Network [OSTI]

    P. R. Silva

    2009-01-07

    The Casimir force between two parallel uncharged closely spaced metallic plates is evaluated in ways alternatives to those usually considered in the literature. In a first approximation we take in account the suppressed quantum numbers of a cubic box, representing a cavity which was cut in a metallic block. We combine these ideas with those of the MIT bag model of hadrons, but adapted to non-relativistic particles. In a second approximation we consider the particles occupying the energy levels of the Bohr atom, so that the Casimir force depends explicitly on the fine structure constant alpha. In both treatments, the mean energies which have explicit dependence on the particle mass and on the maximum occupied quantum number (related to the Fermi level of the system) at the beginning of the calculations, have these dependences mutually canceled at the end of them. Finally by comparing the averaged energies computed in both approximations, we are able to make an estimate of the value of the fine structure constant alpha.

  11. Forces from Connes' geometry

    E-Print Network [OSTI]

    Thomas Schucker

    2007-03-26

    We try to give a pedagogical introduction to Connes' derivation of the standard model of electro-magnetic, weak and strong forces from gravity.

  12. NUCLEAR PROXIMITY FORCES

    E-Print Network [OSTI]

    Randrup, J.

    2011-01-01

    One might summarize of nuclear potential energy has beendegree of freedom) for the nuclear interaction between anyUniversity of California. Nuclear Proximity Forces 'I< at

  13. Chiral three-nucleon forces and pairing in nuclei

    SciTech Connect (OSTI)

    Lesinski, Thomas; Hebeler, K.; Duguet, Thomas C; Schwenk, Achim

    2012-01-01

    We present the first study of pairing in nuclei including three-nucleon forces. We perform systematic calculations of the odd-even mass staggering generated using a microscopic pairing interaction at first order in chiral low-momentum interactions. Significant repulsive contributions from the leading chiral three-nucleon forces are found. Two- and three-nucleon interactions combined account for approximately 70% of the experimental pairing gaps, which leaves room for self-energy and induced interaction effects that are expected to be overall attractive in nuclei.

  14. Protective Force Program Manual

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-12-20

    Provides detailed requirements to supplement DOE O 473.2, PROTECTIVE FORCE PROGRAM, which establishes the requirements and responsibilities for management and operation of the Department of Energy (DOE) Protective Force (PF) Program. Change 1 revised pages in Chapters IV and VI on 12/20/2001.

  15. Atomizing nozzle and process

    DOE Patents [OSTI]

    Anderson, Iver E. (Ames, IA); Figliola, Richard S. (Central, SC); Molnar, Holly M. (Palm Bay, FL)

    1992-06-30

    High pressure atomizing nozzle includes a high pressure gas manifold having a divergent expansion chamber between a gas inlet and arcuate manifold segment to minimize standing shock wave patterns in the manifold and thereby improve filling of the manifold with high pressure gas for improved melt atomization. The atomizing nozzle is especially useful in atomizing rare earth-transition metal alloys to form fine powder particles wherein a majority of the powder particles exhibit particle sizes having near-optimum magnetic properties.

  16. Atomizing nozzle and process

    DOE Patents [OSTI]

    Anderson, I.E.; Figliola, R.S.; Molnar, H.M.

    1993-07-20

    High pressure atomizing nozzle includes a high pressure gas manifold having a divergent expansion chamber between a gas inlet and arcuate manifold segment to minimize standing shock wave patterns in the manifold and thereby improve filling of the manifold with high pressure gas for improved melt atomization. The atomizing nozzle is especially useful in atomizing rare earth-transition metal alloys to form fine powder particles wherein a majority of the powder particles exhibit particle sizes having near-optimum magnetic properties.

  17. Three-dimensional scanning confocal laser microscope

    DOE Patents [OSTI]

    Anderson, R. Rox (Lexington, MA); Webb, Robert H. (Lincoln, MA); Rajadhyaksha, Milind (Charlestown, MA)

    1999-01-01

    A confocal microscope for generating an image of a sample includes a first scanning element for scanning a light beam along a first axis, and a second scanning element for scanning the light beam at a predetermined amplitude along a second axis perpendicular to the first axis. A third scanning element scans the light beam at a predetermined amplitude along a third axis perpendicular to an imaging plane defined by the first and second axes. The second and third scanning element are synchronized to scan at the same frequency. The second and third predetermined amplitudes are percentages of their maximum amplitudes. A selector determines the second and third predetermined amplitudes such that the sum of the percentages is equal to one-hundred percent.

  18. Microscopic Description of Nuclear Fission Dynamics

    E-Print Network [OSTI]

    A. S. Umar; V. E. Oberacker; J. A. Maruhn; P. -G. Reinhard

    2010-03-22

    We discuss possible avenues to study fission dynamics starting from a time-dependent mean-field approach. Previous attempts to study fission dynamics using the time-dependent Hartree-Fock (TDHF) theory are analyzed. We argue that different initial conditions may be needed to describe fission dynamics depending on the specifics of the fission phenomenon and propose various approaches towards this goal. In particular, we provide preliminary calculations for studying fission following a heavy-ion reaction using TDHF with a density contraint. Regarding prompt muon-induced fission, we also suggest a new approach for combining the time-evolution of the muonic wave function with a microscopic treatment of fission dynamics via TDHF.

  19. A microscopic perspective on stochastic thermodynamics

    E-Print Network [OSTI]

    Bernhard Altaner; Jürgen Vollmer

    2015-05-18

    We consider stochastic thermodynamics as a theory of statistical inference for experimentally observed fluctuating time-series. To that end, we introduce a general framework for quantifying the knowledge about the dynamical state of the system on two scales: a fine-grained or microscopic, deterministic and a coarse-grained or mesoscopic, stochastic level of description. For a generic model dynamics, we show how the mathematical expressions for fluctuating entropy changes used in Markovian stochastic thermodynamics emerge naturally. Our ideas are conceptional approaches towards (i) connecting entropy production and its fluctuation relations in deterministic and stochastic systems and (ii) providing a complementary information-theoretic picture to notions of entropy and entropy production in stochastic thermodynamics.

  20. Long working distance incoherent interference microscope

    DOE Patents [OSTI]

    Sinclair, Michael B. (Albuquerque, NM); De Boer, Maarten P. (Albuquerque, NM)

    2006-04-25

    A full-field imaging, long working distance, incoherent interference microscope suitable for three-dimensional imaging and metrology of MEMS devices and test structures on a standard microelectronics probe station. A long working distance greater than 10 mm allows standard probes or probe cards to be used. This enables nanometer-scale 3-dimensional height profiles of MEMS test structures to be acquired across an entire wafer while being actively probed, and, optionally, through a transparent window. An optically identical pair of sample and reference arm objectives is not required, which reduces the overall system cost, and also the cost and time required to change sample magnifications. Using a LED source, high magnification (e.g., 50.times.) can be obtained having excellent image quality, straight fringes, and high fringe contrast.

  1. Microscopic study of Ca$+$Ca fusion

    E-Print Network [OSTI]

    R. Keser; A. S. Umar; V. E. Oberacker

    2012-02-17

    We investigate the fusion barriers for reactions involving Ca isotopes $\\mathrm{^{40}Ca}+\\mathrm{^{40}Ca}$, $\\mathrm{^{40}Ca}+\\mathrm{^{48}Ca}$, and $\\mathrm{^{48}Ca}+\\mathrm{^{48}Ca}$ using the microscopic time-dependent Hartree-Fock theory coupled with a density constraint. In this formalism the fusion barriers are directly obtained from TDHF dynamics. We also study the excitation of the pre-equilibrium GDR for the $\\mathrm{^{40}Ca}+\\mathrm{^{48}Ca}$ system and the associated $\\gamma$-ray emission spectrum. Fusion cross-sections are calculated using the incoming-wave boundary condition approach. We examine the dependence of fusion barriers on collision energy as well as on the different parametrizations of the Skyrme interaction.

  2. Use of Atomic Force Microscopy Force Measurements To Monitor Citrate Displacement by Amines on Gold in

    E-Print Network [OSTI]

    Chan, Derek Y C

    Special Research Centre, University of Melbourne, Parkville, Victoria 3052, Australia, and CSIRO Division of Chemicals and Polymers, Private Bag 10, Rosebank MDC, Clayton, Victoria 3169, Australia Received January 9 in clean, covered petri dishes in a laminar flow hood and rinsed with AR grade ethanol and blown dry

  3. Catalytic Micropumps: Microscopic Convective Fluid Flow and Pattern Timothy R. Kline, Walter F. Paxton, Yang Wang, Darrell Velegol,*, Thomas E. Mallouk,* and

    E-Print Network [OSTI]

    Catalytic Micropumps: Microscopic Convective Fluid Flow and Pattern Formation Timothy R. Kline of the driving forces for developing micro/nanofluidics. Engineering fluid flows at this scale remains a "fuel" can be converted locally at a catalyst surface, possibly eliminating external pumps or power

  4. Single-Atom Extraction by Scanning Tunneling Microscope Tip Crash and

    E-Print Network [OSTI]

    Hla, Saw-Wai

    materials form islands with straight step edges, indicating (Figure 1A) that the amount of heat locally produced. After the tip crash, some of the substrate material is piled up as monolayer-high silver islands-temperature, resulting in formation of silver islands with well-defined shapes.9 In our experiment, the piled up

  5. Long working-distance, incoherent light interference microscope...

    Office of Scientific and Technical Information (OSTI)

    has been developed to address the growing demand for new microsystem characterization tools. The design of the new microscope is similar to that of a Linnik interference...

  6. ORNL's Kalinin awarded Royal Microscopical Society medal | ornl...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Laboratory has been awarded the inaugural Medal for Scanning Probe Microscopy (SPM) by the Royal Microscopical Society (RMS). Kalinin is director of ORNL's Institute for...

  7. PARTICLE ACCELERATORS; 74 ATOMIC AND MOLECULAR PHYSICS; ATOMS...

    Office of Scientific and Technical Information (OSTI)

    74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; ELECTRONS; HELIUM; LIGHT SOURCES; RADIATIONS; STORAGE RINGS; SYNCHROTRONS SYNCHROTRON RADIATION SYNCHROTRONLIGHT SOURCES QUANTUM CHAOS...

  8. Atomic Energy Commission : Atomic Power at Shippingport - 1958 Educational Film

    SciTech Connect (OSTI)

    2013-02-02

    The United States Atomic Energy Commission & Westinghouse Electric Company take us on a tour of an atomic power station.

  9. OOTW Force Design Tools

    SciTech Connect (OSTI)

    Bell, R.E.; Hartley, D.S.III; Packard, S.L.

    1999-05-01

    This report documents refined requirements for tools to aid the process of force design in Operations Other Than War (OOTWs). It recommends actions for the creation of one tool and work on other tools relating to mission planning. It also identifies the governmental agencies and commands with interests in each tool, from whom should come the user advisory groups overseeing the respective tool development activities. The understanding of OOTWs and their analytical support requirements has matured to the point where action can be taken in three areas: force design, collaborative analysis, and impact analysis. While the nature of the action and the length of time before complete results can be expected depends on the area, in each case the action should begin immediately. Force design for OOTWs is not a technically difficult process. Like force design for combat operations, it is a process of matching the capabilities of forces against the specified and implied tasks of the operation, considering the constraints of logistics, transport and force availabilities. However, there is a critical difference that restricts the usefulness of combat force design tools for OOTWs: the combat tools are built to infer non-combat capability requirements from combat capability requirements and cannot reverse the direction of the inference, as is required for OOTWs. Recently, OOTWs have played a larger role in force assessment, system effectiveness and tradeoff analysis, and concept and doctrine development and analysis. In the first Quadrennial Defense Review (QDR), each of the Services created its own OOTW force design tool. Unfortunately, the tools address different parts of the problem and do not coordinate the use of competing capabilities. These tools satisfied the immediate requirements of the QDR, but do not provide a long-term cost-effective solution.

  10. Solidification analysis of a centrifugal atomizer using the Al-32.7wt.% Cu alloy

    SciTech Connect (OSTI)

    Osborne, M.G.

    1998-02-23

    A centrifugal atomizer (spinning disk variety) was designed and constructed for the production of spherical metal powders, 100--1,000 microns in diameter in an inert atmosphere. Initial atomization experiments revealed the need for a better understanding of how the liquid metal was atomized and how the liquid droplets solidified. To investigate particle atomization, Ag was atomized in air and the process recorded on high-speed film. To investigate particle solidification, Al-32.7 wt.% Cu was atomized under inert atmosphere and the subsequent particles were examined microscopically to determine solidification structure and rate. This dissertation details the experimental procedures used in producing the Al-Cu eutectic alloy particles, examination of the particle microstructures, and determination of the solidification characteristics (e.g., solidification rate) of various phases. Finally, correlations are proposed between the operation of the centrifugal atomizer and the observed solidification spacings.

  11. Single Atom Plasmonic Switch

    E-Print Network [OSTI]

    Emboras, Alexandros; Ma, Ping; Haffner, Christian; Luisier, Mathieu; Hafner, Christian; Schimmel, Thomas; Leuthold, Juerg

    2015-01-01

    The atom sets an ultimate scaling limit to Moores law in the electronics industry. And while electronics research already explores atomic scales devices, photonics research still deals with devices at the micrometer scale. Here we demonstrate that photonic scaling-similar to electronics-is only limited by the atom. More precisely, we introduce an electrically controlled single atom plasmonic switch. The switch allows for fast and reproducible switching by means of the relocation of an individual or at most - a few atoms in a plasmonic cavity. Depending on the location of the atom either of two distinct plasmonic cavity resonance states are supported. Experimental results show reversible digital optical switching with an extinction ration of 10 dB and operation at room temperature with femtojoule (fJ) power consumption for a single switch operation. This demonstration of a CMOS compatible, integrated quantum device allowing to control photons at the single-atom level opens intriguing perspectives for a fully i...

  12. Experimental Demonstration of a Synthetic Lorentz Force by Using Radiation Pressure

    E-Print Network [OSTI]

    Šanti?, N; Aumiler, D; Buljan, H; Ban, T

    2015-01-01

    Synthetic magnetism in cold atomic gases opened the doors to many exciting novel physical systems and phenomena. Ubiquitous are the methods used for the creation of synthetic magnetic fields. They include rapidly rotating Bose-Einstein condensates employing the analogy between the Coriolis and the Lorentz force, and laser-atom interactions employing the analogy between the Berry phase and the Aharonov-Bohm phase. Interestingly, radiation pressure - being one of the most common forces induced by light - has not yet been used for synthetic magnetism. We experimentally demonstrate a synthetic Lorentz force, based on the radiation pressure and the Doppler effect, by observing the centre-of-mass motion of a cold atomic cloud. The force is perpendicular to the velocity of the cold atomic cloud, and zero for the cloud at rest. Our novel concept is straightforward to implement in a large volume, for a broad range of velocities, and can be extended to different geometries.

  13. Protective Force Program

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1995-02-13

    To prescribe Department of Energy policy, responsibilities, and requirements for the management and operation of the Protective Force Program. Chg 1 dated 2-13-95. Cancels DOE O 5632.7 and DOE O 5632.8.

  14. Federal Protective Force

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2009-07-15

    This Manual establishes requirements for the management and operation of the Department of Energy (DOE) Federal protective forces (FPFs). Cancels DOE M 470.4-3, Chg 1. Canceled by DOE O 473.3.

  15. Conservative entropic forces

    E-Print Network [OSTI]

    Visser, Matt

    2011-01-01

    Entropic forces have recently attracted considerable attention as ways to reformulate, retrodict, and perhaps even "explain'" classical Newtonian gravity from a rather specific thermodynamic perspective. In this article I point out that if one wishes to reformulate classical Newtonian gravity in terms of an entropic force, then the fact that Newtonian gravity is described by a conservative force places significant constraints on the form of the entropy and temperature functions. (These constraints also apply to entropic reinterpretations of electromagnetism, and indeed to any conservative force derivable from a potential.) The constraints I will establish are sufficient to present real and significant problems for any reasonable variant of Verlinde's entropic gravity proposal, though for technical reasons the constraints established herein do not directly impact on either Jacobson's or Padmanabhan's versions of entropic gravity. In an attempt to resolve these issues, I will extend the usual notion of entropic...

  16. Weak nuclear forces cause the strong nuclear force

    E-Print Network [OSTI]

    E. L. Koschmieder

    2007-12-11

    We determine the strength of the weak nuclear force which holds the lattices of the elementary particles together. We also determine the strength of the strong nuclear force which emanates from the sides of the nuclear lattices. The strong force is the sum of the unsaturated weak forces at the surface of the nuclear lattices. The strong force is then about ten to the power of 6 times stronger than the weak force between two lattice points.

  17. Atom-based coherent quantum-noise cancellation in optomechanics

    E-Print Network [OSTI]

    F. Bariani; H. Seok; S. Singh; M. Vengalattore; P. Meystre

    2015-08-24

    We analyze a quantum force sensor that uses coherent quantum noise cancellation (CQNC) to beat the Standard Quantum Limit (SQL). This sensor, which allows for the continuous, broad-band detection of feeble forces, is a hybrid dual-cavity system comprised of a mesoscopic mechanical resonator optically coupled to an ensemble of ultracold atoms. In contrast to the stringent constraints on dissipation typically associated with purely optical schemes of CQNC, the dissipation rate of the mechanical resonator only needs to be matched to the decoherence rate of the atomic ensemble -- a condition that is experimentally achievable even for the technologically relevant regime of low frequency mechanical resonators with large quality factors. The modular nature of the system further allows the atomic ensemble to aid in the cooling of the mechanical resonator, thereby combining atom-mediated state preparation with sensing deep in the quantum regime.

  18. Atom-based coherent quantum-noise cancellation in optomechanics

    E-Print Network [OSTI]

    Bariani, F; Singh, S; Vengalattore, M; Meystre, P

    2015-01-01

    We analyze a quantum force sensor that uses coherent quantum noise cancellation (CQNC) to beat the Standard Quantum Limit (SQL). This sensor, which allows for the continuous, broad-band detection of feeble forces, is a hybrid dual-cavity system comprised of a mesoscopic mechanical resonator optically coupled to an ensemble of ultracold atoms. In contrast to the stringent constraints on dissipation typically associated with purely optical schemes of CQNC, the dissipation rate of the mechanical resonator only needs to be matched to the decoherence rate of the atomic ensemble -- a condition that is experimentally achievable even for the technologically relevant regime of low frequency mechanical resonators with large quality factors. The modular nature of the system further allows the atomic ensemble to aid in the cooling of the mechanical resonator, thereby combining atom-mediated state preparation with sensing deep in the quantum regime.

  19. CMORE GEMS Report "Microscopes for SEEQS Life Science Curriculum"

    E-Print Network [OSTI]

    CMORE GEMS Report "Microscopes for SEEQS Life Science Curriculum" School for Examining Essential Teacher March 24, 2015 The aim of the project, titled "Microscopes for SEEQS Life Science Curriculum", was to supplement our curriculum with handson scientific experience in our school's inquiry and issuebased

  20. Shear Viscosity Coefficient from Microscopic Models

    E-Print Network [OSTI]

    Azwinndini Muronga

    2003-12-02

    The transport coefficient of shear viscosity is studied for a hadron matter through microscopic transport model, the Ultra--relativistic Quantum Molecular Dynamics (UrQMD), using the Green--Kubo formulas. Molecular--dynamical simulations are performed for a system of light mesons in a box with periodic boundary conditions. Starting from an initial state composed of $\\pi, \\eta ,\\omega ,\\rho ,\\phi$ with a uniform phase--space distribution, the evolution takes place through elastic collisions, production and annihilation. The system approaches a stationary state of mesons and their resonances, which is characterized by common temperature. After equilibration, thermodynamic quantities such as the energy density, particle density, and pressure are calculated. From such an equilibrated state the shear viscosity coefficient is calculated from the fluctuations of stress tensor around equilibrium using Green--Kubo relations. We do our simulations here at zero net baryon density so that the equilibration times depend on the energy density. We do not include hadron strings as degrees of freedom so as to maintain detailed balance. Hence we do not get the saturation of temperature but this leads to longer equilibration times.

  1. Confusion around the tidal force and the centrifugal force

    E-Print Network [OSTI]

    Matsuda, Takuya; Boffin, Henri M J

    2015-01-01

    We discuss the tidal force, whose notion is sometimes misunderstood in the public domain literature. We discuss the tidal force exerted by a secondary point mass on an extended primary body such as the Earth. The tidal force arises because the gravitational force exerted on the extended body by the secondary mass is not uniform across the primary. In the derivation of the tidal force, the non-uniformity of the gravity is essential, and inertial forces such as the centrifugal force are not needed. Nevertheless, it is often asserted that the tidal force can be explained by the centrifugal force. If we literally take into account the centrifugal force, it would mislead us. We therefore also discuss the proper treatment of the centrifugal force.

  2. [Band electronic structures and crystal packing forces

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    We investigated the electronic and structural properties of low-dimensional materials and explored the structure-property correlations governing their physical properties. Progress was made on how to interpret the scanning tunneling microscopy and atomic force microscopy images of layered materials and on how to account for charge density wave instabilities in 2-D metals. Materials studied included transition metal chalcogenides, transition metal halides, organic conducting salts, Mo bronzes, A[sub 2]PdH[sub 2], fullerenes, squarate tetrahydrate polymers Fe, Cu(C[sub 4]O[sub 4])4[center dot]H[sub 2]O, BEDT salts, etc.

  3. Improved graphite furnace atomizer

    DOE Patents [OSTI]

    Siemer, D.D.

    1983-05-18

    A graphite furnace atomizer for use in graphite furnace atomic absorption spectroscopy is described wherein the heating elements are affixed near the optical path and away from the point of sample deposition, so that when the sample is volatilized the spectroscopic temperature at the optical path is at least that of the volatilization temperature, whereby analyteconcomitant complex formation is advantageously reduced. The atomizer may be elongated along its axis to increase the distance between the optical path and the sample deposition point. Also, the atomizer may be elongated along the axis of the optical path, whereby its analytical sensitivity is greatly increased.

  4. The Harnessed Atom

    Broader source: Energy.gov [DOE]

    The Harnessed Atom is a new middle school science, technology, engineering, and math (STEM) curriculum extension that focuses on nuclear science and energy. It offers teachers accurate, unbiased,...

  5. Atomic Collapse Observed

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 | Tags: Hopper, Materials Science Contact: Linda...

  6. Laser-Cooled Lithium Atoms: A New Source for Focused Ion Beams

    E-Print Network [OSTI]

    Laser-Cooled Lithium Atoms: A New Source for Focused Ion Beams P R O J E C T L E A D E R : Jabez Mc E N T S Designed and constructed a laser-cooled, magneto-optical trap-based lithium ion source mounted on a commercial focused ion beam system, creating the world's first lithium ion microscope

  7. Method and apparatus for differential spectroscopic atomic-imaging using scanning tunneling microscopy

    DOE Patents [OSTI]

    Kazmerski, Lawrence L. (Lakewood, CO)

    1990-01-01

    A Method and apparatus for differential spectroscopic atomic-imaging is disclosed for spatial resolution and imaging for display not only individual atoms on a sample surface, but also bonding and the specific atomic species in such bond. The apparatus includes a scanning tunneling microscope (STM) that is modified to include photon biasing, preferably a tuneable laser, modulating electronic surface biasing for the sample, and temperature biasing, preferably a vibration-free refrigerated sample mounting stage. Computer control and data processing and visual display components are also included. The method includes modulating the electronic bias voltage with and without selected photon wavelengths and frequency biasing under a stabilizing (usually cold) bias temperature to detect bonding and specific atomic species in the bonds as the STM rasters the sample. This data is processed along with atomic spatial topography data obtained from the STM raster scan to create a real-time visual image of the atoms on the sample surface.

  8. Producing and Detecting Correlated atoms

    E-Print Network [OSTI]

    Christoph I. Westbrook; Martijn Schellekens; Aurélien Perrin; Valentina Krachmalnicoff; Jose Carlos Viana Gomes; Jean-Baptiste Trebbia; Jérôme Estève; Hong Chang; Isabelle Bouchoule; Denis Boiron; Alain Aspect; Tom Jeltes; John McNamara; Wim Hogervorst; Wim Vassen

    2006-09-04

    We discuss experiments to produce and detect atom correlations in a degenerate or nearly degenerate gas of neutral atoms. First we treat the atomic analog of the celebrated Hanbury Brown Twiss experiment, in which atom correlations result simply from interference effects without any atom interactions.We have performed this experiment for both bosons and fermions. Next we show how atom interactions produce correlated atoms using the atomic analog of spontaneous four-wavemixing. Finally, we briefly mention experiments on a one dimensional gas on an atom chip in which correlation effects due to both interference and interactions have been observed.

  9. Work Force Discipline

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1983-03-23

    The order provides guidance and procedures and states responsibilities for maintaining work force discipline in DOE. Chg 1, dated 3-11-85; Chg 2, dated 1-6-86; Chg 3, dated 3-21-89; Chg 4, dated 8-2-90; Chg 5, dated 3-9-92; Chg 6, dated 8-21-92, cancels Chg 5.

  10. Protective Force Program

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2000-06-30

    Establishes policy, requirements, responsibilities, and authorities, for the management and operation of the Department of Energy (DOE) Protective Force (PF) Program. Extended until 7-7-06 by DOE N 251.64, dated 7-7-05 Cancels: DOE 5632.7A

  11. Contractor Protective Force

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2008-11-05

    This Manual establishes requirements for the management and operation of the U.S. Department of Energy contractor protective forces. Cancels: DOE M 470.4-3 Chg 1, CRD (Attachment 2) only, except for Section C. Canceled by DOE O 473.3.

  12. Direct Aerosol Forcing Uncertainty

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Mccomiskey, Allison

    Understanding sources of uncertainty in aerosol direct radiative forcing (DRF), the difference in a given radiative flux component with and without aerosol, is essential to quantifying changes in Earth's radiation budget. We examine the uncertainty in DRF due to measurement uncertainty in the quantities on which it depends: aerosol optical depth, single scattering albedo, asymmetry parameter, solar geometry, and surface albedo. Direct radiative forcing at the top of the atmosphere and at the surface as well as sensitivities, the changes in DRF in response to unit changes in individual aerosol or surface properties, are calculated at three locations representing distinct aerosol types and radiative environments. The uncertainty in DRF associated with a given property is computed as the product of the sensitivity and typical measurement uncertainty in the respective aerosol or surface property. Sensitivity and uncertainty values permit estimation of total uncertainty in calculated DRF and identification of properties that most limit accuracy in estimating forcing. Total uncertainties in modeled local diurnally averaged forcing range from 0.2 to 1.3 W m-2 (42 to 20%) depending on location (from tropical to polar sites), solar zenith angle, surface reflectance, aerosol type, and aerosol optical depth. The largest contributor to total uncertainty in DRF is usually single scattering albedo; however decreasing measurement uncertainties for any property would increase accuracy in DRF. Comparison of two radiative transfer models suggests the contribution of modeling error is small compared to the total uncertainty although comparable to uncertainty arising from some individual properties.

  13. Direct Aerosol Forcing Uncertainty

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Mccomiskey, Allison

    2008-01-15

    Understanding sources of uncertainty in aerosol direct radiative forcing (DRF), the difference in a given radiative flux component with and without aerosol, is essential to quantifying changes in Earth's radiation budget. We examine the uncertainty in DRF due to measurement uncertainty in the quantities on which it depends: aerosol optical depth, single scattering albedo, asymmetry parameter, solar geometry, and surface albedo. Direct radiative forcing at the top of the atmosphere and at the surface as well as sensitivities, the changes in DRF in response to unit changes in individual aerosol or surface properties, are calculated at three locations representing distinct aerosol types and radiative environments. The uncertainty in DRF associated with a given property is computed as the product of the sensitivity and typical measurement uncertainty in the respective aerosol or surface property. Sensitivity and uncertainty values permit estimation of total uncertainty in calculated DRF and identification of properties that most limit accuracy in estimating forcing. Total uncertainties in modeled local diurnally averaged forcing range from 0.2 to 1.3 W m-2 (42 to 20%) depending on location (from tropical to polar sites), solar zenith angle, surface reflectance, aerosol type, and aerosol optical depth. The largest contributor to total uncertainty in DRF is usually single scattering albedo; however decreasing measurement uncertainties for any property would increase accuracy in DRF. Comparison of two radiative transfer models suggests the contribution of modeling error is small compared to the total uncertainty although comparable to uncertainty arising from some individual properties.

  14. Wolter mirror microscope : novel neutron focussing and imaging optic

    E-Print Network [OSTI]

    Bagdasarova, Yelena S. (Yelena Sergeyevna)

    2010-01-01

    In this thesis, I investigated the effectiveness of a Wolter Type I neutron microscope as a focusing and imaging device for thermal and cold neutrons sources by simulating the performance of the optics in a standard neutron ...

  15. From Microscopic Gravitational Waves to the Quantum Indeterminism

    E-Print Network [OSTI]

    Van Thuan, Vo

    2015-01-01

    Based on an extended space-time symmetry a new attempt to search for links between general relativity and quantum mechanics is proposed. A simplified cylindrical model of gravitational geometrical dynamics leads to a microscopic geodesic description of strongly curved extradimensional space-time which implies a duality between an emission law of microscopic gravitational waves and the quantum mechanical equations of free elementary particles. Consequently, the Heisenberg indeterminism would originate from the time-space curvatures.

  16. From Microscopic Gravitational Waves to the Quantum Indeterminism

    E-Print Network [OSTI]

    Vo Van Thuan

    2015-06-30

    Based on an extended space-time symmetry a new attempt to search for links between general relativity and quantum mechanics is proposed. A simplified cylindrical model of gravitational geometrical dynamics leads to a microscopic geodesic description of strongly curved extradimensional space-time which implies a duality between an emission law of microscopic gravitational waves and the quantum mechanical equations of free elementary particles. Consequently, the Heisenberg indeterminism would originate from the time-space curvatures.

  17. Magneto-Optical Cooling of Atoms Mark G. Raizen1

    E-Print Network [OSTI]

    Magneto-Optical Cooling of Atoms Mark G. Raizen1 , Dmitry Budker2,3 , Simon Rochester3 , Julia, Weizmann Institute of Science, Rehovot, Israel Abstract We propose an alternative method to laser cooling and stimulated optical transitions, combined with magnetic forces can be used to cool the translational motion

  18. Atom chip apparatus for experiments with ultracold rubidium and potassium gases

    SciTech Connect (OSTI)

    Ivory, M. K.; Ziltz, A. R.; Fancher, C. T.; Pyle, A. J.; Sensharma, A.; Chase, B.; Field, J. P.; Garcia, A.; Aubin, S.; Jervis, D.

    2014-04-15

    We present a dual chamber atom chip apparatus for generating ultracold {sup 87}Rb and {sup 39}K atomic gases. The apparatus produces quasi-pure Bose-Einstein condensates of 10{sup 4} {sup 87}Rb atoms in an atom chip trap that features a dimple and good optical access. We have also demonstrated production of ultracold {sup 39}K and subsequent loading into the chip trap. We describe the details of the dual chamber vacuum system, the cooling lasers, the magnetic trap, the multicoil magnetic transport system, the atom chip, and two optical dipole traps. Due in part to the use of light-induced atom desorption, the laser cooling chamber features a sufficiently good vacuum to also support optical dipole trap-based experiments. The apparatus is well suited for studies of atom-surface forces, quantum pumping and transport experiments, atom interferometry, novel chip-based traps, and studies of one-dimensional many-body systems.

  19. Limits on weak magnetic confinement of neutral atoms C. A. Sackett*

    E-Print Network [OSTI]

    Sackett, Cass

    Limits on weak magnetic confinement of neutral atoms C. A. Sackett* Physics Department, University It is shown that when a magnetic field is used to support neutral atoms against the gravitational force mg, the total curvature of the field magnitude B must be larger than m2 g2 / 2 2 B , where is the magnetic

  20. Impact of graphene coating on the atom-plate interaction

    E-Print Network [OSTI]

    G. L. Klimchitskaya; V. M. Mostepanenko

    2014-06-23

    Using the recently proposed quantum electrodynamical formalism, we calculate the Casimir-Polder free energies and forces between the ground state atoms of Rb, Na, Cs and He${}^{\\ast}$ and the plates made of Au, Si, sapphire and fused silica coated with a graphene sheet. It is shown that the graphene coating has no effect on the Casimir-Polder interaction for metallic plates, but influences significantly for plates made of dielectric materials. The influence of graphene coating increases with decreasing static dielectric permittivity of the plate material and the characteristic frequency of an atomic dynamic polarizability. Simple analytic expressions for the classical limit of the Casimir-Polder free energy and force between an atom and a graphene-coated plate are obtained. From the comparison with the results of numerical computations, the application region of these expressions is determined.

  1. Force Modulator System

    SciTech Connect (OSTI)

    Redmond Clark

    2009-04-30

    Many metal parts manufacturers use large metal presses to shape sheet metal into finished products like car body parts, jet wing and fuselage surfaces, etc. These metal presses take sheet metal and - with enormous force - reshape the metal into a fully formed part in a manner of seconds. Although highly efficient, the forces involved in forming metal parts also damage the press itself, limit the metals used in part production, slow press operations and, when not properly controlled, cause the manufacture of large volumes of defective metal parts. To date, the metal-forming industry has not been able to develop a metal-holding technology that allows full control of press forces during the part forming process. This is of particular importance in the automotive lightweighting efforts under way in the US automotive manufacturing marketplace. Metalforming Controls Technology Inc. (MC2) has developed a patented press control system called the Force Modulator that has the ability to control these press forces, allowing a breakthrough in stamping process control. The technology includes a series of hydraulic cylinders that provide controlled tonnage at all points in the forming process. At the same time, the unique cylinder design allows for the generation of very high levels of clamping forces (very high tonnages) in very small spaces; a requirement for forming medium and large panels out of HSS and AHSS. Successful production application of these systems testing at multiple stamping operations - including Ford and Chrysler - has validated the capabilities and economic benefits of the system. Although this technology has been adopted in a number of stamping operations, one of the primary barriers to faster adoption and application of this technology in HSS projects is system cost. The cost issue has surfaced because the systems currently in use are built for each individual die as a custom application, thus driving higher tooling costs. This project proposed to better marry the die-specific Force Modulator technology with stamping presses in the form of a press cushion. This system would be designed to operate the binder ring for multiple parts, thus cutting the per-die cost of the technology. This study reports the results of technology field application. This project produced the following conclusions: (1) The Force Modulator system is capable of operating at very high tempos in the stamping environment; (2) The company can generate substantial, controlled holding tonnage (binder ring pressure) necessary to hold high strength steel parts for proper formation during draw operations; (3) A single system can be designed to operate with a family of parts, thus significantly reducing the per-die cost of a FM system; (4) High strength steel parts made with these systems appear to show significant quality improvements; (5) The amounts of steel required to make these parts is typically less than the amounts required with traditional blank-holding technologies; and (6) This technology will aid in the use of higher strength steels in auto and truck production, thus reducing weight and improving fuel efficiency.

  2. Is gravity entropic force?

    E-Print Network [OSTI]

    Rong-Jia Yang

    2014-09-11

    If we assume that the source of thermodynamic system, $\\rho$ and $p$, are also the source of gravity, thermal quantities, such as entropy, temperature, and chemical potential, can induce effects of gravity, or gravity can induce thermal effects. We find only for systems with constant temperature and zero chemical potential, gravity can be seen as an entropic force. The case for Newtonian approximation is discussed.

  3. Forced Granular Orifice Flow

    E-Print Network [OSTI]

    Zheng Peng; Hepeng Zheng; Yimin Jiang

    2009-09-06

    The flow of granular material through an orifice is studied experimentally as a function of force $F$ pushing the flow. It is found that the flow rate increases linearly with $F$ -- a new, unexpected result that is in contrast to the usual view that $F$, completely screened by an arch formed around the orifice, has no way of altering the rate. Employing energy balance, we show that this behavior results mainly from dissipation in the granular material.

  4. Optical atomic magnetometer

    DOE Patents [OSTI]

    Budker, Dmitry; Higbie, James; Corsini, Eric P.

    2013-11-19

    An optical atomic magnetometers is provided operating on the principles of nonlinear magneto-optical rotation. An atomic vapor is optically pumped using linearly polarized modulated light. The vapor is then probed using a non-modulated linearly polarized light beam. The resulting modulation in polarization angle of the probe light is detected and used in a feedback loop to induce self-oscillation at the resonant frequency.

  5. Atomizing nozzle and method

    DOE Patents [OSTI]

    Ting, Jason (Ames, IA); Anderson, Iver E. (Ames, IA); Terpstra, Robert L. (Ames, IA)

    2000-03-16

    A high pressure close-coupled gas atomizing nozzle includes multiple discrete gas jet discharge orifices having aerodynamically designed convergent-divergent geometry with an first converging section communicated to a gas supply manifold and to a diverging section by a constricted throat section to increase atomizing gas velocity. The gas jet orifices are oriented at gas jet apex angle selected relative to the melt supply tip apex angle to establish a melt aspiration condition at the melt supply tip.

  6. A Master equation for force distributions in polydisperse frictional particles

    E-Print Network [OSTI]

    Kuniyasu Saitoh; Vanessa Magnanimo; Stefan Luding

    2015-05-28

    An incremental evolution equation, i.e. a Master equation in statistical mechanics, is introduced for force distributions in polydisperse frictional particle packings. As basic ingredients of the Master equation, the conditional probability distributions of particle overlaps are determined by molecular dynamics simulations. Interestingly, tails of the distributions become much narrower in the case of frictional particles than frictionless particles, implying that correlations of overlaps are strongly reduced by microscopic friction. Comparing different size distributions, we find that the tails are wider for the wider distribution.

  7. Bosonization approach for "atomic collapse" in graphene

    E-Print Network [OSTI]

    Aya Kagimura; Tetsuya Onogi

    2015-08-26

    We study quantum electrodynamics with 2+1 dimensional massless Dirac fermion around a Coulomb impurity. Around a large charge with atomic number Z > 137, the QED vacuum is expected to collapse due to the strong Coulombic force. While the relativistic quantum mechanics fails to make reliable predictions for the fate of the vacuum, the heavy ion collision experiment also does not give clear understanding of this system. Recently, the "atomic collapse" resonances were observed on graphene where an artificial nuclei can be made. In this paper, we present our nonperturbative study of the vacuum structure of the quasiparticles in graphene with a charge impurity which contains multi-body effect using bosonization method.

  8. Bosonization approach for "atomic collapse" in graphene

    E-Print Network [OSTI]

    Aya Kagimura; Tetsuya Onogi

    2015-08-02

    We study quantum electrodynamics with 2+1 dimensional massless Dirac fermion around a Coulomb impurity. Around a large charge with atomic number Z > 137, the QED vacuum is expected to collapse due to the strong Coulombic force. While the relativistic quantum mechanics fails to make reliable predictions for the fate of the vacuum, the heavy ion collision experiment also does not give clear understanding of this system. Recently,the "atomic collapse" resonances were observed on graphene where an artificial nuclei can be made. In this paper, we present our non-perturbative study of the vacuum strucuture of the quasiparticles in graphene with a charge impurity which contains multi-body effect using bosonization method.

  9. Bosonization approach for "atomic collapse" in graphene

    E-Print Network [OSTI]

    Kagimura, Aya

    2015-01-01

    We study quantum electrodynamics with 2+1 dimensional massless Dirac fermion around a Coulomb impurity. Around a large charge with atomic number Z > 137, the QED vacuum is expected to collapse due to the strong Coulombic force. While the relativistic quantum mechanics fails to make reliable predictions for the fate of the vacuum, the heavy ion collision experiment also does not give clear understanding of this system. Recently,the "atomic collapse" resonances were observed on graphene where an artificial nuclei can be made. In this paper, we present our non-perturbative study of the vacuum strucuture of the quasiparticles in graphene with a charge impurity which contains multi-body effect using bosonization method.

  10. Non-equilibrium structure and dynamics in a microscopic model of thin film active gels

    E-Print Network [OSTI]

    D. A. Head; W. J. Briels; G. Gompper

    2014-02-26

    In the presence of ATP, molecular motors generate active force dipoles that drive suspensions of protein filaments far from thermodynamic equilibrium, leading to exotic dynamics and pattern formation. Microscopic modelling can help to quantify the relationship between individual motors plus filaments to organisation and dynamics on molecular and supra-molecular length scales. Here we present results of extensive numerical simulations of active gels where the motors and filaments are confined between two infinite parallel plates. Thermal fluctuations and excluded-volume interactions between filaments are included. A systematic variation of rates for motor motion, attachment and detachment, including a differential detachment rate from filament ends, reveals a range of non-equilibrium behaviour. Strong motor binding produces structured filament aggregates that we refer to as asters, bundles or layers, whose stability depends on motor speed and differential end-detachment. The gross features of the dependence of the observed structures on the motor rate and the filament concentration can be captured by a simple one-filament model. Loosely bound aggregates exhibit super-diffusive mass transport, where filament translocation scales with lag time with non-unique exponents that depend on motor kinetics. An empirical data collapse of filament speed as a function of motor speed and end-detachment is found, suggesting a dimensional reduction of the relevant parameter space. We conclude by discussing the perspectives of microscopic modelling in the field of active gels.

  11. Self-consistent Green's functions with three-body forces

    E-Print Network [OSTI]

    Arianna Carbone

    2014-07-24

    The present thesis aims at studying the properties of symmetric nuclear and pure neutron matter from a Green's functions point of view, including two-body and three-body chiral forces. An extended self-consistent Green's function formalism is defined to consistently incorporate three-body forces in the many-body calculations. The effect of three-nucleon interactions is included via the construction of a dressed two-body density dependent force. This is obtained performing an average of the leading order three-body terms in the chiral effective field theory expansion. The dressed force corresponds to the use of an in-medium propagator in the average which takes into account the correlations characterizing the system at each stage of the many-body calculation. The total energy of the system is obtained by means of a modified Galitskii-Migdal-Koltun sumrule to correctly account for the effect of three-body forces. Microscopic as well as macroscopic properties of symmetric nuclear and pure neutron matter are analyzed in detailed.

  12. Atom-interferometry constraints on dark energy

    E-Print Network [OSTI]

    Hamilton, Paul; Haslinger, Philipp; Simmons, Quinn; Müller, Holger; Khoury, Justin

    2015-01-01

    If dark energy---which drives the accelerated expansion of the universe---consists of a new light scalar field, it might be detectable as a "fifth force" between normal-matter objects, in potential conflict with precision tests of gravity. There has, however, been much theoretical progress in developing theories with screening mechanisms, which can evade detection by suppressing forces in regions of high density, such as the laboratory. One prominent example is the chameleon field. We reduce the effect of this screening mechanism by probing the chameleon with individual atoms rather than bulk matter. Using a cesium matter-wave interferometer near a spherical mass in an ultra-high vacuum chamber, we constrain a wide class of dynamical dark energy theories. Our experiment excludes a range of chameleon theories that reproduce the observed cosmic acceleration.

  13. Atom-interferometry constraints on dark energy

    E-Print Network [OSTI]

    Paul Hamilton; Matt Jaffe; Philipp Haslinger; Quinn Simmons; Holger Müller; Justin Khoury

    2015-07-02

    If dark energy --- which drives the accelerated expansion of the universe --- consists of a light scalar field, it might be detectable as a "fifth force" between normal-matter objects, in potential conflict with precision tests of gravity. Chameleon fields and other theories with screening mechanisms, however, can evade these tests by suppressing the forces in regions of high density, such as the laboratory. Using a cesium matter-wave interferometer near a spherical mass in an ultra-high vacuum chamber, we reduce the screening mechanism by probing the field with individual atoms rather than bulk matter. Thus, we constrain a wide class of dark energy theories, including a range of chameleon and other theories that reproduce the observed cosmic acceleration.

  14. Universal bosonic tetramers of dimer-atom-atom structure

    E-Print Network [OSTI]

    A. Deltuva

    2012-03-28

    Unstable four-boson states having an approximate dimer-atom-atom structure are studied using momentum-space integral equations for the four-particle transition operators. For a given Efimov trimer the universal properties of the lowest associated tetramer are determined. The impact of this tetramer on the atom-trimer and dimer-dimer collisions is analyzed. The reliability of the three-body dimer-atom-atom model is studied.

  15. Universal bosonic tetramers of dimer-atom-atom structure

    E-Print Network [OSTI]

    Deltuva, A

    2012-01-01

    Unstable four-boson states having an approximate dimer-atom-atom structure are studied using momentum-space integral equations for the four-particle transition operators. For a given Efimov trimer the universal properties of the lowest associated tetramer are determined. The impact of this tetramer on the atom-trimer and dimer-dimer collisions is analyzed. The reliability of the three-body dimer-atom-atom model is studied.

  16. Atomic vapor laser isotope separation

    SciTech Connect (OSTI)

    Stern, R.C.; Paisner, J.A.

    1986-08-15

    The atomic vapor laser isotope separation (AVLIS) process for the enrichment of uranium is evaluated. (AIP)

  17. Work Force Restructuring Activities

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyThe U.S.Lacledeutilities.EnergyKirstin AlberiComputerMathewsWeiWork Force

  18. Probing Atomic Structure and Majorana Wavefunctions in Mono-Atomic Fe-chains on Superconducting Pb-Surface

    E-Print Network [OSTI]

    Pawlak, Remy; Klinovaja, Jelena; Meier, Tobias; Kawai, Shigeki; Glatzel, Thilo; Loss, Daniel; Meyer, Ernst

    2015-01-01

    Motivated by the striking promise of quantum computation, Majorana bound states (MBSs) in solid-state systems have attracted wide attention in recent years. In particular, the wavefunction localization of MBSs is a key feature and crucial for their future implementation as qubits. Here, we investigate the spatial and electronic characteristics of topological superconducting chains of iron atoms on the surface of Pb(110) by combining scanning tunneling microscopy (STM) and atomic force microscopy (AFM). We demonstrate that the Fe chains are mono-atomic, structured in a linear fashion, and exhibit zero-bias conductance peaks at their ends which we interprete as signature for a Majorana bound state. Spatially resolved conductance maps of the atomic chains reveal that the MBSs are well localized at the chain ends (below 25 nm), with two localization lengths as predicted by theory. Our observation lends strong support to use MBSs in Fe chains as qubits for quantum computing devices.

  19. Iowa Powder Atomization Technologies

    ScienceCinema (OSTI)

    None

    2013-03-01

    The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

  20. Iowa Powder Atomization Technologies

    SciTech Connect (OSTI)

    2012-01-01

    The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

  1. High-stability cryogenic scanning tunneling microscope based on a closed-cycle cryostat

    SciTech Connect (OSTI)

    Hackley, Jason D.; Kislitsyn, Dmitry A.; Beaman, Daniel K.; Nazin, George V.; Ulrich, Stefan

    2014-10-15

    We report on the design and operation of a cryogenic ultra-high vacuum (UHV) scanning tunneling microscope (STM) coupled to a closed-cycle cryostat (CCC). The STM is thermally linked to the CCC through helium exchange gas confined inside a volume enclosed by highly flexible rubber bellows. The STM is thus mechanically decoupled from the CCC, which results in a significant reduction of the mechanical noise transferred from the CCC to the STM. Noise analysis of the tunneling current shows current fluctuations up to 4% of the total current, which translates into tip-sample distance variations of up to 1.5 picometers. This noise level is sufficiently low for atomic-resolution imaging of a wide variety of surfaces. To demonstrate this, atomic-resolution images of Au(111) and NaCl(100)/Au(111) surfaces, as well as of carbon nanotubes deposited on Au(111), were obtained. Thermal drift analysis showed that under optimized conditions, the lateral stability of the STM scanner can be as low as 0.18 Å/h. Scanning Tunneling Spectroscopy measurements based on the lock-in technique were also carried out, and showed no detectable presence of noise from the closed-cycle cryostat. Using this cooling approach, temperatures as low as 16 K at the STM scanner have been achieved, with the complete cool-down of the system typically taking up to 12 h. These results demonstrate that the constructed CCC-coupled STM is a highly stable instrument capable of highly detailed spectroscopic investigations of materials and surfaces at the atomic scale.

  2. Laser Probing of Neutron-Rich Nuclei in Light Atoms

    E-Print Network [OSTI]

    Z. -T. Lu; P. Mueller; G. W. F. Drake; W. Noertershaeuser; Steven C. Pieper; Z. -C. Yan

    2013-07-10

    The neutron-rich 6He and 8He isotopes exhibit an exotic nuclear structure that consists of a tightly bound 4He-like core with additional neutrons orbiting at a relatively large distance, forming a halo. Recent experimental efforts have succeeded in laser trapping and cooling these short-lived, rare helium atoms, and have measured the atomic isotope shifts along the 4He-6He-8He chain by performing laser spectroscopy on individual trapped atoms. Meanwhile, the few-electron atomic structure theory, including relativistic and QED corrections, has reached a comparable degree of accuracy in the calculation of the isotope shifts. In parallel efforts, also by measuring atomic isotope shifts, the nuclear charge radii of lithium and beryllium isotopes have been studied. The techniques employed were resonance ionization spectroscopy on neutral, thermal lithium atoms and collinear laser spectroscopy on beryllium ions. Combining advances in both atomic theory and laser spectroscopy, the charge radii of these light halo nuclei have now been determined for the first time independent of nuclear structure models. The results are compared with the values predicted by a number of nuclear structure calculations, and are used to guide our understanding of the nuclear forces in the extremely neutron-rich environment.

  3. Stemi 1000/2000/2000-C Stereo Microscopes

    E-Print Network [OSTI]

    Kleinfeld, David

    12 Stemi 1000/2000/2000-C Stereo Microscopes Operating Manual #12;Unless expressly authorized in the event of granting of patents or registration of a utility model. #12;Stemi 1000, Stemi 2000, Stemi 2000, Stemi 2000, Stemi 2000-C 12/98 B 40-002 eII 4 CARE AND TROUBLESHOOTING 4.1 Care 4

  4. Mechanisms of Nickel Sorption on Pyrophyllite: Macroscopic and Microscopic Approaches

    E-Print Network [OSTI]

    Sparks, Donald L.

    Mechanisms of Nickel Sorption on Pyrophyllite: Macroscopic and Microscopic Approaches Andre M of the sorption mechanisms of heavy metals on soil mineral surfaces is therefore of fundamental importance. This study examined Ni(Il) sorption mechanisms on pyrophyllite. The removal of Ni from solution was studied

  5. Neutrinoless double beta decay in the microscopic interacting boson model

    SciTech Connect (OSTI)

    Iachello, F. [Center for Theoretical Physics, Sloane Physics Laboratory Yale University New Haven, CT 06520-8120 (United States)

    2009-11-09

    The results of a calculation of the nuclear matrix elements for neutrinoless double beta decay in the closure approximation in several nuclei within the framework of the microscopic interacting boson model (IBM-2) are presented and compared with those calculated in the shell model (SM) and quasiparticle random phase approximation (QRPA)

  6. Laser excited confocal microscope fluorescence scanner and method

    DOE Patents [OSTI]

    Mathies, R.A.; Peck, K.

    1992-02-25

    A fluorescent scanner is designed for scanning the fluorescence from a fluorescence labeled separated sample on a sample carrier. The scanner includes a confocal microscope for illuminating a predetermined volume of the sample carrier and/or receiving and processing fluorescence emissions from the volume to provide a display of the separated sample. 8 figs.

  7. Adhesion and cohesion in structures containing suspended microscopic polymeric films

    E-Print Network [OSTI]

    Shan, Wanliang

    Adhesion and cohesion in structures containing suspended microscopic polymeric films W.L. Shan a 2011 Accepted 12 December 2011 Available online 16 December 2011 Keywords: Adhesive strength Cohesive presents a novel technique for the characterization of adhesion and cohesion in suspended micro

  8. An interchangeable scanning Hall probe/scanning SQUID microscope

    SciTech Connect (OSTI)

    Tang, Chiu-Chun; Lin, Hui-Ting; Wu, Sing-Lin [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Chen, Tse-Jun; Wang, M. J. [Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 10617, Taiwan (China); Ling, D. C. [Department of Physics, Tamkang University, Tamsui Dist., New Taipei City 25137, Taiwan (China); Chi, C. C.; Chen, Jeng-Chung [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan (China)

    2014-08-15

    We have constructed a scanning probe microscope for magnetic imaging, which can function as a scanning Hall probe microscope (SHPM) and as a scanning SQUID microscope (SSM). The scanning scheme, applicable to SHPM and SSM, consists of a mechanical positioning (sub) micron-XY stage and a flexible direct contact to the sample without a feedback control system for the Z-axis. With the interchangeable capability of operating two distinct scanning modes, our microscope can incorporate the advantageous functionalities of the SHPM and SSM with large scan range up to millimeter, high spatial resolution (?4 ?m), and high field sensitivity in a wide range of temperature (4.2 K-300 K) and magnetic field (10{sup ?7} T-1 T). To demonstrate the capabilities of the system, we present magnetic images scanned with SHPM and SSM, including a RbFeB magnet and a nickel grid pattern at room temperature, surface magnetic domain structures of a La{sub 2/3}Ca{sub 1/3}MnO{sub 3} thin film at 77 K, and superconducting vortices in a striped niobium film at 4.2 K.

  9. 1 INTRODUCTION 2 2 MICROSCOPIC MODELING OF HBTs 3

    E-Print Network [OSTI]

    Pulfrey, David L.

    in the engineering-design of high-frequency and high-speed devices. At the microscopic level, the emphasis, is related to the unity gain, power cut-off frequency, fmax. These two frequencies are the main performance into a large-signal equivalent circuit suitable for the simulation of HBTs in switching applications. 2 #12

  10. Dynamic microscopic theory of fusion using DC-TDHF

    SciTech Connect (OSTI)

    Umar, A. S.; Oberacker, V. E.; Keser, R.; Maruhn, J. A.; Reinhard, P.-G.

    2012-10-20

    The density-constrained time-dependent Hartree-Fock (DC-TDHF) theory is a fully microscopic approach for calculating heavy-ion interaction potentials and fusion cross sections below and above the fusion barrier. We discuss recent applications of DC-TDHF method to fusion of light and heavy systems.

  11. Ultracold Atoms: How Quantum Field Theory Invaded Atomic Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ultracold Atoms: How Quantum Field Theory Invaded Atomic Physics Eric Braaten Ohio State University May 6, 2015 4:00 p.m. (coffee @ 3:30) The development of the technology for...

  12. Primary Atomization of a Liquid Jet in Crossflow

    E-Print Network [OSTI]

    Rana, Sandeep

    2010-01-01

    In this fluid dynamics video, we present a visualization of the primary atomization of a turbulent liquid jet injected into a turbulent gaseous crossflow. It is based on a detailed numerical simulation of the primary atomization region of the jet using a finite volume, balanced force, incompressible LES/DNS flow solver coupled to a Refined Level Set Grid (RLSG) solver to track the phase interface position. The visualization highlights the two distinct breakup modes of the jet: the column breakup mode of the main liquid column and the ligament breakup mode on the sides of the jet and highlights the complex evolution of the phase interface geometry.

  13. Dilution and resonance enhanced repulsion in non-equilibrium fluctuation forces

    E-Print Network [OSTI]

    Giuseppe Bimonte; Thorsten Emig; Matthias Kruger; Mehran Kardar

    2011-07-08

    In equilibrium, forces induced by fluctuations of the electromagnetic field between electrically polarizable objects (microscopic or macroscopic) in vacuum are always attractive. The force may, however, become repulsive for microscopic particles coupled to thermal baths with different temperatures. We demonstrate that this non-equilibrium repulsion can be realized also between macroscopic objects, as planar slabs, if they are kept at different temperatures. It is shown that repulsion can be enhanced by (i) tuning of material resonances in the thermal region, and by (ii) reducing the dielectric contrast due to "dilution". This can lead to stable equilibrium positions. We discuss the realization of these effects for aerogels, yielding repulsion down to sub-micron distances at realistic porosities.

  14. Dilution and resonance enhanced repulsion in non-equilibrium fluctuation forces

    E-Print Network [OSTI]

    Bimonte, Giuseppe; Kruger, Matthias; Kardar, Mehran

    2011-01-01

    In equilibrium, forces induced by fluctuations of the electromagnetic field between electrically polarizable objects (microscopic or macroscopic) in vacuum are always attractive. The force may, however, become repulsive for microscopic particles coupled to thermal baths with different temperatures. We demonstrate that this non-equilibrium repulsion can be realized also between macroscopic objects, as planar slabs, if they are kept at different temperatures. It is shown that repulsion can be enhanced by (i) tuning of material resonances in the thermal region, and by (ii) reducing the dielectric contrast due to "dilution". This can lead to stable equilibrium positions. We discuss the realization of these effects for aerogels, yielding repulsion down to sub-micron distances at realistic porosities.

  15. Quantum anti-centrifugal force

    E-Print Network [OSTI]

    M. A. Cirone; K. Rzazewski; W. P. Schleich; F. Straub; J. A. Wheeler

    2001-08-16

    In a two-dimensional world a free quantum particle of vanishing angular momentum experiences an attractive force. This force originates from a modification of the classical centrifugal force due to the wave nature of the particle. For positive energies the quantum anti-centrifugal force manifests itself in a bunching of the nodes of the energy wave functions towards the origin. For negative energies this force is sufficient to create a bound state in a two-dimensional delta function potential. In a counter-intuitive way the attractive force pushes the particle away from the location of the delta function potential. As a consequence, the particle is localized in a band-shaped domain around the origin

  16. Microscopic description of neutron emission rates in compound nuclei

    E-Print Network [OSTI]

    Yi Zhu; Junchen Pei

    2014-11-02

    The neutron emission rates in thermal excited nuclei are conventionally described by statistical models with a phenomenological level density parameter that depends on excitation energies, deformations and mass regions. In the microscopic view of hot nuclei, the neutron emission rates can be determined by the external neutron gas densities without any free parameters. Therefore the microscopic description of thermal neutron emissions is desirable that can impact several understandings such as survival probabilities of superheavy compound nuclei and neutron emissivity in reactors. To describe the neutron emission rates microscopically, the external thermal neutron gases are self-consistently obtained based on the Finite-Temperature Hartree-Fock-Bogoliubov (FT-HFB) approach. The results are compared with the statistical model to explore the connections between the FT-HFB approach and the statistical model. The Skyrme FT-HFB equation is solved by HFB-AX in deformed coordinate spaces. Based on the FT-HFB approach, the thermal properties and external neutron gas are properly described with the self-consistent gas substraction procedure. Then neutron emission rates can be obtained based on the densities of external neutron gases. The thermal statistical properties of $^{238}$U and $^{258}$U are studied in detail in terms of excitation energies. The thermal neutron emission rates in $^{238, 258}$U and superheavy compound nuclei $_{112}^{278}$Cn and $_{114}^{292}$Fl are calculated, which agree well with the statistical model by adopting an excitation-energy-dependent level density parameter. The coordinate-space FT-HFB approach can provide reliable microscopic descriptions of neutron emission rates in hot nuclei, as well as microscopic constraints on the excitation energy dependence of level density parameters for statistical models.

  17. Continuous Forcing Data, Darwin, Australia

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Jakob, Christian

    2010-09-22

    Long term, large scale continuous forcing data set for three complete wet seasons (2004-2005, 2005-2006 and 2006-2007) in Darwin, Australia.

  18. Force As A Momentum Current

    SciTech Connect (OSTI)

    Munera, Hector A.

    2010-07-28

    Advantages of a neo-Cartesian approach to classical mechanics are noted. If conservation of linear momentum is the fundamental principle, Newton's three laws become theorems. A minor paradox in static Newtonian mechanics is identified, and solved by reinterpreting force as a current of momentum. Contact force plays the role of a mere midwife in the exchange of momentum; however, force cannot be eliminated from physics because it provides the numerical value for momentum current. In this sense, in a neo-Cartesian formulation of mechanics the concept of force becomes strengthened rather than weakened.

  19. Continuous Forcing Data, Darwin, Australia

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Jakob, Christian

    Long term, large scale continuous forcing data set for three complete wet seasons (2004-2005, 2005-2006 and 2006-2007) in Darwin, Australia.

  20. Air Force Renewable Energy Programs

    Broader source: Energy.gov [DOE]

    Presentation covers Air Force Renewable Energy Programs and is given at the Spring 2011 Federal Utility Partnership Working Group (FUPWG) meeting.

  1. Constraints on muon-specific dark forces

    E-Print Network [OSTI]

    Savely G. Karshenboim; David McKeen; Maxim Pospelov

    2014-01-23

    The recent measurement of the Lamb shift in muonic hydrogen allows for the most precise extraction of the charge radius of the proton which is currently in conflict with other determinations based on $e-p$ scattering and hydrogen spectroscopy. This discrepancy could be the result of some new muon-specific force with O(1-100) MeV force carrier---in this paper we concentrate on vector mediators. Such an explanation faces challenges from the constraints imposed by the $g-2$ of the muon and electron as well as precision spectroscopy of muonic atoms. In this work we complement the family of constraints by calculating the contribution of hypothetical forces to the muonium hyperfine structure. We also compute the two-loop contribution to the electron parity violating amplitude due to a muon loop, which is sensitive to the muon axial-vector coupling. Overall, we find that the combination of low-energy constraints favors the mass of the mediator to be below 10 MeV, and that a certain degree of tuning is required between vector and axial-vector couplings of new vector particles to muons in order to satisfy constraints from muon $g-2$. However, we also observe that in the absence of a consistent standard model embedding, high energy weak-charged processes accompanied by the emission of new vector particles are strongly enhanced by $(E/m_V)^2$, with $E$ a characteristic energy scale and $m_V$ the mass of the mediator. In particular, leptonic $W$ decays impose the strongest constraints on such models completely disfavoring the remainder of the parameter space.

  2. Environmental Performance Characterization of Atomic Layer Deposition

    E-Print Network [OSTI]

    Yuan, Chris; Dornfeld, David

    2008-01-01

    Rahtu and R. Gordon. “Atomic layer deposition of transitionoxide films grown by atomic layer deposition from iodide andand S. M. George. “Atomic layer deposition of ultrathin and

  3. A microfabricated atomic clock

    SciTech Connect (OSTI)

    Knappe, Svenja; Shah, Vishal; Schwindt, Peter D.D.; Hollberg, Leo; Kitching, John; Liew, Li-Anne; Moreland, John [Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305-3328 (United States); Electromagnetics Division, National Institute of Standards and Technology, Boulder, Colorado 80305-3328 (United States)

    2004-08-30

    Fabrication techniques usually applied to microelectromechanical systems (MEMS) are used to reduce the size and operating power of the core physics assembly of an atomic clock. With a volume of 9.5 mm{sup 3}, a fractional frequency instability of 2.5x10{sup -10} at 1 s of integration, and dissipating less than 75 mW of power, the device has the potential to bring atomically precise timing to hand-held, battery-operated devices. In addition, the design and fabrication process allows for wafer-level assembly of the structures, enabling low-cost mass-production of thousands of identical units with the same process sequence, and easy integration with other electronics.

  4. Nanomanipulation and nanofabrication with multi-probe STM: From individual atoms to nanowires

    SciTech Connect (OSTI)

    Qin, Shengyong; Kim, Tae Hwan; Wang, Zhouhang; Li, An-Ping

    2012-01-01

    The wide variety of nanoscale structures and devices demands novel tools for handling, assembly, and fabrication at nanoscopic positioning precision. The manipulation tools should allow for in situ characterization and testing of fundamental building blocks, such as nanotubes and nanowires, as they are built into functional devices. In this paper, a bottom-up technique for nanomanipulation and nanofabrication is reported by using a 4-probe scanning tunneling microscope (STM) combined with a scanning electron microscope (SEM). The applications of this technique are demonstrated in a variety of nanosystems, from manipulating individual atoms to bending, cutting, breaking carbon nanofibers, and constructing nanodevices for electrical characterizations. The combination of the wide field of view of SEM, the atomic position resolution of STM, and the flexibility of multiple scanning probes is expected to be a valuable tool for rapid prototyping in the nanoscience and nanotechnology.

  5. Coherent population transfer and optical dipole force by chirped Gaussian femtosecond pulses in four level {sup 87}Rb

    SciTech Connect (OSTI)

    Chakraborty, Subhadeep, E-mail: aksarma@iitg.ernet.in; Sarma, Amarendra K., E-mail: aksarma@iitg.ernet.in [Department of Physics, Indian Institute of Technology Guwahati, Guwahati-781039, Assam (India)

    2014-10-15

    We report coherent population transfer(CPT) in a four level atomic system, coupled by three chirped Gaussian femtosecond pulses. CPT is studied under two specific conditions beyond the RWA. It is observed that nearly complete population transfer to the states |3> and |4> can be achieved by maintaining proper resonance condition and judiciously choosing the laser parameters. In addition to this, the transverse optical dipole force on the four-level atomic system is numerically studied. The transverse force provides an acceleration to an atom which is eight order of magnitude higher than earth’s gravitational acceleration g. The force changes from a focusing force to a defocusing one as the initial population changes from the ground states to the excited states.

  6. Atomic configuration of irradiation-induced planar defects in 3C-SiC

    SciTech Connect (OSTI)

    Lin, Y. R. [Department of Engineering and System Science, National Tsing-Hua University, Hsinchu 30013, Taiwan (China); National Synchrotron Radiation Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan (China); Ho, C. Y. [Institute of Nuclear Engineering and Science, National Tsing-Hua University, Hsinchu 30013, Taiwan (China); Hsieh, C. Y.; Chang, M. T.; Lo, S. C. [Material and Chemical Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan (China); Chen, F. R. [Department of Engineering and System Science, National Tsing-Hua University, Hsinchu 30013, Taiwan (China); Kai, J. J., E-mail: ceer0001@gmail.com [Department of Engineering and System Science, National Tsing-Hua University, Hsinchu 30013, Taiwan (China); Institute of Nuclear Engineering and Science, National Tsing-Hua University, Hsinchu 30013, Taiwan (China)

    2014-03-24

    The atomic configuration of irradiation-induced planar defects in single crystal 3C-SiC at high irradiation temperatures was shown in this research. A spherical aberration corrected scanning transmission electron microscope provided images of individual silicon and carbon atoms by the annular bright-field (ABF) method. Two types of irradiation-induced planar defects were observed in the ABF images including the extrinsic stacking fault loop with two offset Si-C bilayers and the intrinsic stacking fault loop with one offset Si-C bilayer. The results are in good agreement with images simulated under identical conditions.

  7. Whole-Cell Sensing for a Harmful Bloom-Forming Microscopic Alga by Measuring Antibody-Antigen Forces

    E-Print Network [OSTI]

    2006-01-01

    I. I NTRODUCTION INGLE-CELLED microalgae play an essentialabundance of speci?c microalgae [10]–[13]. Early applicationand prokary- otic microalgae [3], [14]–[17]. These

  8. Characterization of patinas by means of microscopic techniques

    SciTech Connect (OSTI)

    Vazquez-Calvo, C.

    2007-11-15

    Many stone-made historic buildings have a yellowish layer called 'patina' on their external surface. In some cases, it is due to the natural ageing of the stone caused by chemical-physical reactions between the surface of the stone and the environment, and in other cases it is the result of biological activity. The origin of these patinas can be also be due to ancient protective treatments. The use of organic additives, such as protein-based compounds, in lime or gypsum-based patinas is a traditional technique, which has been used in past centuries for the conservation and protection of stone materials. The thinness of the patinas ensures that microscopic techniques are irreplaceable for their analysis. Optical Microscopy, Fluorescence Microscopy, Scanning Electron Microscopy together with an Energy Dispersive X-ray Spectrometer, and Electron Microprobe are the microscopic techniques used for the characterization of these coverings, providing very useful information on their composition, texture and structure.

  9. Prospective study on microscopic potential with Gogny interaction

    E-Print Network [OSTI]

    Blanchon, G; Arellano, H F

    2015-01-01

    We present our current studies and our future plans on microscopic potential based on effective nucleon-nucleon interaction and many-body theory. This framework treats in an unified way nuclear structure and reaction. It offers the opportunity to link the underlying effective interaction to nucleon scattering observables. The more consistently connected to a variety of reaction and structure experimental data the framework will be, the more constrained effective interaction will be. As a proof of concept, we present some recent results for both neutron and proton scattered from spherical target nucleus, namely 40 Ca, using the Gogny D1S interaction. Possible fruitful crosstalks between microscopic potential, phenomenological potential and effective interaction are exposed. We then draw some prospective plans for the forthcoming years including scattering from spherical nuclei experiencing pairing correlations, scattering from axially deformed nuclei, and new effective interaction with reaction constraints.

  10. Simulation of High Density Pedestrian Flow: Microscopic Model

    E-Print Network [OSTI]

    Dridi, Mohamed H

    2015-01-01

    In recent years modelling crowd and evacuation dynamics has become very important, with increasing huge numbers of people gathering around the world for many reasons and events. The fact that our global population grows dramatically every year and the current public transport systems are able to transport large amounts of people, heightens the risk of crowd panic or crush. Pedestrian models are based on macroscopic or microscopic behaviour. In this paper, we are interested in developing models that can be used for evacuation control strategies. This model will be based on microscopic pedestrian simulation models, and its evolution and design requires a lot of information and data. The people stream will be simulated, based on mathematical models derived from empirical data about pedestrian flows. This model is developed from image data bases, so called empirical data, taken from a video camera or data obtained using human detectors. We consider the individuals as autonomous particles interacting through socia...

  11. Motion-reversal in a simple microscopic swimmer

    E-Print Network [OSTI]

    A. Alexander-Katz

    2007-05-18

    We study the motion of a microscopic swimmer composed of a semiflexible polymer anchored at the surface of a magnetic sphere using hydrodynamic simulations and scaling arguments. The swimmer is driven by a rotating magnetic field, and displays forward and backward motion depending on the value of the rotational frequency. In particular, the system exhibits forward thrust for frequencies below a critical frequency $\\omega^*$, while above $\\omega^*$ the motion is reversed.

  12. An Advanced Ultra-Low Temperature Scanning Probe Microscope

    E-Print Network [OSTI]

    An Advanced Ultra-Low Temperature Scanning Probe Microscope P R O J E C T L E A D E R : Joseph); Steven Blankenship, Alan Band (NIST) G O A L To develop an ultra-high vacuum, ultra-low temperature, high of subpicometer stability and can operate in ultra-high vacuum at 10 mK, and in magnetic fields up to 15 T

  13. Investigation of Microscopic Materials Limitations of Superconducting RF Cavities

    SciTech Connect (OSTI)

    Anlage, Steven

    2014-07-23

    The high-field performance of SRF cavities is often limited by breakdown events below the intrinsic limiting surface fields of Nb, and there is abundant evidence that these breakdown events are localized in space inside the cavity. Also, there is a lack of detailed understanding of the causal links between surface treatments and ultimate RF performance at low temperatures. An understanding of these links would provide a clear roadmap for improvement of SRF cavity performance, and establish a cause-and-effect ‘RF materials science’ of Nb. We propose two specific microscopic approaches to addressing these issues. First is a spatially-resolved local microwave-microscope probe that operates at SRF frequencies and temperatures to discover the microscopic origins of breakdown, and produce quantitative measurements of RF critical fields of coatings and films. Second, RF Laser Scanning Microscopy (LSM) has allowed visualization of RF current flow and sources of nonlinear RF response in superconducting devices with micro-meter spatial resolution. The LSM will be used in conjunction with surface preparation and characterization techniques to create definitive links between physical and chemical processing steps and ultimate cryogenic microwave performance. We propose to develop RF laser scanning microscopy of small-sample Nb pieces to establish surface-processing / RF performance relations through measurement of RF current distributions on micron-length scales and low temperatures.

  14. Optics and interferometry with atoms and molecules

    E-Print Network [OSTI]

    Cronin, Alexander D.

    Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic ...

  15. Backaction-Driven Transport of Bloch Oscillating Atoms in Ring Cavities

    E-Print Network [OSTI]

    J. Goldwin; B. Prasanna Venkatesh; D. H. J. O'Dell

    2014-08-19

    We predict that an atomic Bose-Einstein condensate strongly coupled to an intracavity optical lattice can undergo resonant tunneling and directed transport when a constant and uniform bias force is applied. The bias force induces Bloch oscillations, causing amplitude and phase modulation of the lattice which resonantly modifies the site-to-site tunneling. For the right choice of parameters a net atomic current is generated. The transport velocity can be oriented oppositely to the bias force, with its amplitude and direction controlled by the detuning between the pump laser and the cavity. The transport can also be enhanced through imbalanced pumping of the two counter-propagating running wave cavity modes. Our results add to the cold atoms quantum simulation toolbox, with implications for quantum sensing and metrology.

  16. Near-Field Magneto-Optical Microscope (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Publication: United States Language: English Subject: 47 OTHER INSTRUMENTATION; FIBER OPTICS; MAGNETIC FIELDS; MICROSCOPES; POLARIZATION; RESOLUTION; DESIGN; OPERATION Word Cloud...

  17. Near-Field Magneto-Optical Microscope (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 47 OTHER INSTRUMENTATION; FIBER OPTICS; MAGNETIC FIELDS; MICROSCOPES; POLARIZATION; RESOLUTION; DESIGN; OPERATION...

  18. A next-generation EUV Fresnel zoneplate mask-imaging microscope

    E-Print Network [OSTI]

    Goldberg, Kenneth A.

    2012-01-01

    A next-generation EUV Fresnel zoneplate mask-imaginghigh-magnification all-EUV Fresnel zoneplate microscope, the

  19. UV-light microscope: improvements in optical imaging for a secondary ion mass spectrometer

    E-Print Network [OSTI]

    Meyers, Stephen R.

    UV-light microscope: improvements in optical imaging for a secondary ion mass spectrometer Noriko T­10 mm. However, the original reflected light microscope of the CAMECA IMS 1280 SIMS had an optical at the mm scale. We modified the optical microscope to use ultraviolet (UV) light illumination and UV

  20. An EUV Fresnel zoneplate mask-imaging microscope for lithography generations reaching 8 nm

    E-Print Network [OSTI]

    An EUV Fresnel zoneplate mask-imaging microscope for lithography generations reaching 8 nm Kenneth lithography design rules. The proposed microscope features an array of user-selectable Fresnel zoneplate-EUV, Fresnel zoneplate microscope, the AIT has been in the vanguard of high-resolution EUV mask imaging

  1. Compact cryogenic Kerr microscope for time-resolved studies of electron spin transport in microstructures

    E-Print Network [OSTI]

    van der Wal, Caspar H.

    Compact cryogenic Kerr microscope for time-resolved studies of electron spin transport with 1 m spatial resolution. The microscope was designed to study spin transport, a critical issue-temperature optical microscope, elec- tromagnet and cryogenic cell with cold finger to measure continuous-wave cw

  2. Stochastic force in gravitational systems

    E-Print Network [OSTI]

    A. Del Popolo

    2001-05-10

    In this paper I study the probability distribution of the gravitational force in gravitational systems through numerical experiments. I show that Kandrup's (1980) and Antonuccio-Delogu & Atrio-Barandela's (1992) theories describe correctly the stochastic force probability distribution respectively in inhomogeneous and clustered systems. I find equations for the probability distribution of stochastic forces in finite systems, both homogeneous and clustered, which I use to compare the theoretical predictions with Montecarlo simulations of spherically symmetric systems. The agreement between theoretical predictions and simulations proves to be quite satisfactory.

  3. Self-Assembly of Polymer Nano-Elements on Sapphire

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    overhead view (top) of cylindrical block-coploymer structures, consisting of a central polymer (blue) linked to a surrounding polymer (red). An atomic-force microscope image...

  4. Atomic Energy Commission Takes Over Responsibility for all Atomic...

    National Nuclear Security Administration (NNSA)

    Takes Over Responsibility for all Atomic Energy Programs | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile...

  5. A 30 mK, 13.5 T scanning tunneling microscope with two independent tips

    SciTech Connect (OSTI)

    Roychowdhury, Anita [Laboratory for Physical Sciences, College Park, Maryland 20742 (United States) [Laboratory for Physical Sciences, College Park, Maryland 20742 (United States); Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, Maryland 20740 (United States); Gubrud, M. A.; Dana, R.; Dreyer, M. [Laboratory for Physical Sciences, College Park, Maryland 20742 (United States)] [Laboratory for Physical Sciences, College Park, Maryland 20742 (United States); Anderson, J. R.; Lobb, C. J.; Wellstood, F. C. [Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, Maryland 20740 (United States)] [Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, Maryland 20740 (United States)

    2014-04-15

    We describe the design, construction, and performance of an ultra-low temperature, high-field scanning tunneling microscope (STM) with two independent tips. The STM is mounted on a dilution refrigerator and operates at a base temperature of 30 mK with magnetic fields of up to 13.5 T. We focus on the design of the two-tip STM head, as well as the sample transfer mechanism, which allows in situ transfer from an ultra high vacuum preparation chamber while the STM is at 1.5 K. Other design details such as the vibration isolation and rf-filtered wiring are also described. Their effectiveness is demonstrated via spectral current noise characteristics and the root mean square roughness of atomic resolution images. The high-field capability is shown by the magnetic field dependence of the superconducting gap of Cu{sub x}Bi{sub 2}Se{sub 3}. Finally, we present images and spectroscopy taken with superconducting Nb tips with the refrigerator at 35 mK that indicate that the effective temperature of our tips/sample is approximately 184 mK, corresponding to an energy resolution of 16 ?eV.

  6. Prediction of vehicle impact forces 

    E-Print Network [OSTI]

    Kaderka, Darrell Laine

    1990-01-01

    PREDICTION OF VEHICLE IMPACT FORCES A Thesis by DARRELL LAINE KADERKA Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1990 Major Subject...: Civil Engineering PREDICTION OF VEHICLE IMPACT FORCES A Thesis by DARRELL LAINE KADERKA Approved as to style and content by: C. Eugene Buth (Chair of Committee) W. ynn Beason (Member) I? D n E. B ay (Member) es T. P. Yao (Departmen Head) May...

  7. Quantum transport in ultracold atoms

    E-Print Network [OSTI]

    Chih-Chun Chien; Sebastiano Peotta; Massimiliano Di Ventra

    2015-04-11

    Ultracold atoms confined by engineered magnetic or optical potentials are ideal systems for studying phenomena otherwise difficult to realize or probe in the solid state because their atomic interaction strength, number of species, density, and geometry can be independently controlled. This review focuses on quantum transport phenomena in atomic gases that mirror and oftentimes either better elucidate or show fundamental differences with those observed in mesoscopic and nanoscopic systems. We discuss significant progress in performing transport experiments in atomic gases, contrast similarities and differences between transport in cold atoms and in condensed matter systems, and survey inspiring theoretical predictions that are difficult to verify in conventional setups. These results further demonstrate the versatility offered by atomic systems in the study of nonequilibrium phenomena and their promise for novel applications.

  8. Dwell-Time Distribution Analysis of Polyprotein Unfolding Using Force-Clamp Spectroscopy

    E-Print Network [OSTI]

    Fernandez, Julio M.

    Department of Biological Sciences, Columbia University, New York, New York 10027 ABSTRACT Using the recently be accounted for suggests alternative unfolding barriers in the energy landscape of the protein. This method), as well as the presence of alternative unfolding energy barriers. Force-clamp spectroscopy using atomic

  9. Is Gravity an Entropic Force?

    E-Print Network [OSTI]

    Shan Gao

    2011-07-16

    The remarkable connections between gravity and thermodynamics seem to imply that gravity is not fundamental but emergent, and in particular, as Verlinde suggested, gravity is probably an entropic force. In this paper, we will argue that the idea of gravity as an entropic force is debatable. It is shown that there is no convincing analogy between gravity and entropic force in Verlinde's example. Neither holographic screen nor test particle satisfies all requirements for the existence of entropic force in a thermodynamics system. Furthermore, we show that the entropy increase of the screen is not caused by its statistical tendency to increase entropy as required by the existence of entropic force, but in fact caused by gravity. Therefore, Verlinde's argument for the entropic origin of gravity is problematic. In addition, we argue that the existence of a minimum size of spacetime, together with the Heisenberg uncertainty principle in quantum theory, may imply the fundamental existence of gravity as a geometric property of spacetime. This may provide a further support for the conclusion that gravity is not an entropic force.

  10. "Centrifugal Forces," Spring, 2015 Centrifugal Forces: Reading Russia's Regional Identities and Initiatives

    E-Print Network [OSTI]

    Huang, Wei

    "Centrifugal Forces," Spring, 2015 Centrifugal Forces: Reading Russia's Regional Identities and articulating their particular identities and interests. Proposals for "Centrifugal Forces" will resist "Moscow and periphery. "Centrifugal Forces" will be a three-day conference offering broad interdisciplinary perspectives

  11. String model of the Hydrogen Atom

    E-Print Network [OSTI]

    Omar Yepez

    2007-01-31

    A non-moving electron hydrogen model is proposed, resolving a long standing contradiction (94 years) in the hydrogen atom. This, however, forces to not use the "in an orbit point particle kinetic energy" as the phenomenon responsible for the atom stability. The repulsion between the masses of the electron and proton is what is responsible of such stability. The mass of the electron is a field fully described by the uncertainty principle through the confinement of the particle, which is also consistent with the general theory of relativity that states: "mass-energy tells the space how to bend". Ergo, mass exerts a tension on its surrounding space and the lighter the mass the larger the space it will occupy. Based on this concept it is proposed that the orbital is the electron. The electron's orbitals are just the electron's different ways of intersecting the space; with different magnetic momenta. The coupling of this momenta with the magnetic moment of the proton finally explains the hyperfine structure of the hydrogen spectrum with an overwhelming simplicity

  12. Microscopic self-energy calculations and dispersive optical-model potentials

    E-Print Network [OSTI]

    S. J. Waldecker; C. Barbieri; W. H. Dickhoff

    2011-05-21

    Nucleon self-energies for 40Ca, 48Ca, 60Ca isotopes are generated with the microscopic Faddeev-random-phase approximation (FRPA). These self-energies are compared with potentials from the dispersive optical model (DOM) that were obtained from fitting elastic-scattering and bound-state data for 40Ca and 48Ca. The \\textit{ab initio} FRPA is capable of explaining many features of the empirical DOM potentials including their nucleon asymmetry dependence. The comparison furthermore provides several suggestions to improve the functional form of the DOM potentials, including among others the exploration of parity and angular momentum dependence. The non-locality of the FRPA imaginary self-energy, illustrated by a substantial orbital angular momentum dependence, suggests that future DOM fits should consider this feature explicitly. The roles of the nucleon-nucleon tensor force and charge-exchange component in generating the asymmetry dependence of the FPRA self-energies are explored. The global features of the FRPA self-energies are not strongly dependent on the choice of realistic nucleon-nucleon interaction.

  13. Microscopic theory of elastico-mechanoluminescent smart materials

    SciTech Connect (OSTI)

    Chandra, B. P., E-mail: bpchandra4@yahoo.co.in; Jha, Piyush [Department of Postgraduate Studies and Research in Physics and Electronics, Rani Durgavati University, Jabalpur 482001, MP (India); Chandra, V. K. [Department of Electrical and Electronics Engineering, Chhatrapati Shivaji Institute of Technology, Shivaji Nagar, Kolihapuri, Durg 491001, CG (India)

    2014-01-20

    The concepts of piezoelectric field dependence of the detrapping probability and lifetime of charge carriers in traps are developed. The charge carriers in traps become unstable after a particular piezoelectric field whereby more number of charge carriers are detrapped with increasing piezoelectric field. The detrapped electrons tunnel to the energy level of the hole-captured activator ions lying adjacent to the conduction band or tunnel to conduction band. Subsequently, luminescence is induced by the electron-hole recombination. Using these concepts microscopic theory of elastico-mechanoluminescent smart materials is explored. Present study may be useful in tailoring intense elastico-mechanoluminescent materials needed for different applications.

  14. Relativistic Viscous Fluid Description of Microscopic Black Hole Wind

    E-Print Network [OSTI]

    J. I. Kapusta

    2001-05-25

    Microscopic black holes explode with their temperature varying inversely as their mass. Such explosions would lead to the highest temperatures in the present universe, all the way to the Planck energy. Whether or not a quasi-stationary shell of matter undergoing radial hydrodynamic expansion surrounds such black holes is been controversial. In this paper relativistic viscous fluid equations are applied to the problem. It is shown that a self-consistent picture emerges of a fluid just marginally kept in local thermal equilibrium; viscosity is a crucial element of the dynamics.

  15. A Kirkpatrick-Baez microscope for the National Ignition Facility

    SciTech Connect (OSTI)

    Pickworth, L. A., E-mail: pickworth1@llnl.gov; McCarville, T.; Decker, T.; Pardini, T.; Ayers, J.; Bell, P.; Bradley, D.; Brejnholt, N. F.; Izumi, N.; Mirkarimi, P.; Pivovaroff, M.; Smalyuk, V.; Vogel, J.; Walton, C. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Kilkenny, J. [General Atomics, San Diego, California 92121 (United States)

    2014-11-15

    Current pinhole x ray imaging at the National Ignition Facility (NIF) is limited in resolution and signal throughput to the detector for Inertial Confinement Fusion applications, due to the viable range of pinhole sizes (10–25 ?m) that can be deployed. A higher resolution and throughput diagnostic is in development using a Kirkpatrick-Baez microscope system (KBM). The system will achieve <9 ?m resolution over a 300 ?m field of view with a multilayer coating operating at 10.2 keV. Presented here are the first images from the uncoated NIF KBM configuration demonstrating high resolution has been achieved across the full 300 ?m field of view.

  16. Microscopic Calculation of Heavy-Ion Potentials Based on TDHF

    E-Print Network [OSTI]

    A. S. Umar; V. E. Oberacker; J. A. Maruhn; P. -G. Reinhard\\

    2011-06-17

    We discuss the implementation and results of a recently developed microscopic method for calculating ion-ion interaction potentials and fusion cross-sections. The method uses the TDHF evolution to obtain the instantaneous many-body collective state using a density constraint. The ion-ion potential as well as the coordinate dependent mass are calculated from these states. The method fully accounts for the dynamical processes present in the TDHF time-evolution and provides a parameter-free way of calculating fusion cross-sections.

  17. Cation Transport in Polymer Electrolytes: A Microscopic Approach

    E-Print Network [OSTI]

    A. Maitra; A. Heuer

    2007-05-11

    A microscopic theory for cation diffusion in polymer electrolytes is presented. Based on a thorough analysis of molecular dynamics simulations on PEO with LiBF$_4$ the mechanisms of cation dynamics are characterised. Cation jumps between polymer chains can be identified as renewal processes. This allows us to obtain an explicit expression for the lithium ion diffusion constant D_{Li} by invoking polymer specific properties such as the Rouse dynamics. This extends previous phenomenological and numerical approaches. In particular, the chain length dependence of D_{Li} can be predicted and compared with experimental data. This dependence can be fully understood without referring to entanglement effects.

  18. Concurrent in situ ion irradiation transmission electron microscope

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hattar, K.; Bufford, D. C.; Buller, D. L.

    2014-08-29

    An in situ ion irradiation transmission electron microscope has been developed and is operational at Sandia National Laboratories. This facility permits high spatial resolution, real time observation of electron transparent samples under ion irradiation, implantation, mechanical loading, corrosive environments, and combinations thereof. This includes the simultaneous implantation of low-energy gas ions (0.8–30 keV) during high-energy heavy ion irradiation (0.8–48 MeV). In addition, initial results in polycrystalline gold foils are provided to demonstrate the range of capabilities.

  19. Microscopic analysis of order parameters in nuclear quantum phase transitions

    SciTech Connect (OSTI)

    Li, Z. P.; Niksic, T.; Vretenar, D.; Meng, J.

    2009-12-15

    Microscopic signatures of nuclear ground-state shape phase transitions in Nd isotopes are studied using excitation spectra and collective wave functions obtained by diagonalization of a five-dimensional Hamiltonian for quadrupole vibrational and rotational degrees of freedom, with parameters determined by constrained self-consistent relativistic mean-field calculations for triaxial shapes. As a function of the physical control parameter, the number of nucleons, energy gaps between the ground state and the excited vibrational states with zero angular momentum, isomer shifts, and monopole transition strengths exhibit sharp discontinuities at neutron number N=90, which is characteristic of a first-order quantum phase transition.

  20. Microscopic Description of Induced Nuclear Fission (Conference) | SciTech

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(JournalspectroscopyReport) |(Patent) |monitoring.(Patent)Connect Microscopic

  1. Einstein's Hydrogen Atom

    E-Print Network [OSTI]

    Y. S. Kim

    2011-12-02

    In 1905, Einstein formulated his special relativity for point particles. For those particles, his Lorentz covariance and energy-momentum relation are by now firmly established. How about the hydrogen atom? It is possible to perform Lorentz boosts on the proton assuming that it is a point particle. Then what happens to the electron orbit? The orbit could go through an elliptic deformation, but it is not possible to understand this problem without quantum mechanics, where the orbit is a standing wave leading to a localized probability distribution. Is this concept consistent with Einstein's Lorentz covariance? Dirac, Wigner, and Feynman contributed important building blocks for understanding this problem. The remaining problem is to assemble those blocks to construct a Lorentz-covariant picture of quantum bound states based on standing waves. It is shown possible to assemble those building blocks using harmonic oscillators.

  2. Intermodulation electrostatic force microscopy for imaging surface photo-voltage

    SciTech Connect (OSTI)

    Borgani, Riccardo Forchheimer, Daniel; Thorén, Per-Anders; Haviland, David B.; Bergqvist, Jonas; Inganäs, Olle

    2014-10-06

    We demonstrate an alternative to Kelvin Probe Force Microscopy for imaging surface potential. The open-loop, single-pass technique applies a low-frequency AC voltage to the atomic force microscopy tip while driving the cantilever near its resonance frequency. Frequency mixing due to the nonlinear capacitance gives intermodulation products of the two drive frequencies near the cantilever resonance, where they are measured with high signal to noise ratio. Analysis of this intermodulation response allows for quantitative reconstruction of the contact potential difference. We derive the theory of the method, validate it with numerical simulation and a control experiment, and we demonstrate its utility for fast imaging of the surface photo-voltage on an organic photo-voltaic material.

  3. Spin-Flavor van der Waals Forces and NN interaction

    SciTech Connect (OSTI)

    Alvaro Calle Cordon, Enrique Ruiz Arriola

    2011-12-01

    A major goal in Nuclear Physics is the derivation of the Nucleon-Nucleon (NN) interaction from Quantum Chromodynamics (QCD). In QCD the fundamental degrees of freedom are colored quarks and gluons which are confined to form colorless strongly interacting hadrons. Because of this the resulting nuclear forces at sufficiently large distances correspond to spin-flavor excitations, very much like the dipole excitations generating the van der Waals (vdW) forces acting between atoms. We study the Nucleon-Nucleon interaction in the Born-Oppenheimer approximation at second order in perturbation theory including the Delta resonance as an intermediate state. The potential resembles strongly chiral potentials computed either via soliton models or chiral perturbation theory and has a van der Waals like singularity at short distances which is handled by means of renormalization techniques. Results for the deuteron are discussed.

  4. Atomic Scale Characterization of Compound Semiconductors Using Atom Probe Tomography

    SciTech Connect (OSTI)

    Gorman, B. P.; Norman, A. G.; Lawrence, D.; Prosa, T.; Guthrey, H.; Al-Jassim, M.

    2011-01-01

    Internal interfaces are critical in determining the performance of III-V multijunction solar cells. Studying these interfaces with atomic resolution using a combination of transmission electron microscopy (TEM), atom probe tomography (APT), and density functional calculations enables a more fundamental understanding of carrier dynamics in photovoltaic (PV) device structures. To achieve full atomic scale spatial and chemical resolution, data acquisition parameters in laser pulsed APT must be carefully studied to eliminate surface diffusion. Atom probe data with minimized group V ion clustering and expected stoichiometry can be achieved by adjusting laser pulse power, pulse repetition rate, and specimen preparation parameters such that heat flow away from the evaporating surface is maximized. Applying these improved analysis conditions to III-V based PV gives an atomic scale understanding of compositional and dopant profiles across interfaces and tunnel junctions and the initial stages of alloy clustering and dopant accumulation. Details on APT experimental methods and future in-situ instrumentation developments are illustrated.

  5. Integration of contractile forces during tissue invagination

    E-Print Network [OSTI]

    Martin, Adam C.

    Contractile forces generated by the actomyosin cytoskeleton within individual cells collectively generate tissue-level force during epithelial morphogenesis. During Drosophila mesoderm invagination, pulsed actomyosin ...

  6. Forces in electromagnetic field and gravitational field

    E-Print Network [OSTI]

    Zihua Weng

    2011-03-31

    The force can be defined from the linear momentum in the gravitational field and electromagnetic field. But this definition can not cover the gradient of energy. In the paper, the force will be defined from the energy and torque in a new way, which involves the gravitational force, electromagnetic force, inertial force, gradient of energy, and some other new force terms etc. One of these new force terms can be used to explain why the solar wind varies velocity along the magnetic force line in the interplanetary space between the sun and the earth.

  7. Spin noise spectroscopy to probe quantum states of ultracold fermionic atomic gases

    E-Print Network [OSTI]

    Bogdan Mihaila; Scott A. Crooker; Krastan B. Blagoev; Dwight G. Rickel; Peter B. Littlewood; Darryl L. Smith

    2006-01-01

    Ultracold alkali atoms provide experimentally accessible model systems for probing quantum states that manifest themselves at the macroscopic scale. Recent experimental realizations of superfluidity in dilute gases of ultracold fermionic (half-integer spin) atoms offer exciting opportunities to directly test theoretical models of related many-body fermion systems that are inaccessible to experimental manipulation, such as neutron stars and quark-gluon plasmas. However, the microscopic interactions between fermions are potentially quite complex, and experiments in ultracold gases to date cannot clearly distinguish between the qualitatively different microscopic models that have been proposed. Here, we theoretically demonstrate that optical measurements of electron spin noise -- the intrinsic, random fluctuations of spin -- can probe the entangled quantum states of ultracold fermionic atomic gases and unambiguously reveal the detailed nature of the interatomic interactions. We show that different models predict different sets of resonances in the noise spectrum, and once the correct effective interatomic interaction model is identified, the line-shapes of the spin noise can be used to constrain this model. Further, experimental measurements of spin noise in classical (Boltzmann) alkali vapors are used to estimate the expected signal magnitudes for spin noise measurements in ultracold atom systems and to show that these measurements are feasible.

  8. The Atomic City / The Magic of the Atom - 1950's Atomic Energy Commission Documentary

    SciTech Connect (OSTI)

    2012-06-04

    The story of American cities located near atomic power plants, and steps taken monitoring radiation to ensure the safety of the public who live nearby. .

  9. Cavity Nonlinear Optics at Low Photon Numbers from Collective Atomic Motion

    E-Print Network [OSTI]

    Subhadeep Gupta; Kevin L. Moore; Kater W. Murch; Dan M. Stamper-Kurn

    2007-09-05

    We report on Kerr nonlinearity and dispersive optical bistability of a Fabry-Perot optical resonator due to the displacement of ultracold atoms trapped within. In the driven resonator, such collective motion is induced by optical forces acting upon up to $10^5$ $^{87}$Rb atoms prepared in the lowest band of a one-dimensional intracavity optical lattice. The longevity of atomic motional coherence allows for strongly nonlinear optics at extremely low cavity photon numbers, as demonstrated by the observation of both branches of optical bistability at photon numbers below unity.

  10. The use of atomic level stress to characterize the structure of irradiated iron

    SciTech Connect (OSTI)

    Egami, Takeshi [ORNL] [ORNL; Ojha, Madhusudan [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK); Nicholson, Donald M. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Odbadrakh, Khorgolkhuu [ORNL] [ORNL; Radhakrishnan, Bala [ORNL] [ORNL; Stoller, Roger E [ORNL] [ORNL

    2012-01-01

    The behaviour of irradiated material near a primary knock on atom immediately after impact is of great importance for designing reactor materials. Currently, molecular dynamics simulations with classical force fields provide the foundation for understanding the resulting cascade. However, modern density functional calculations can now treat large enough numbers of atoms that they can provide additional details of the magnetic and electronic nature of irradiated samples. In this paper we calculate from first principles the atomic level stresses for an instantaneous configuration following the initiation of a low energy cascade in iron.

  11. Nonlocal microscopic theory of quantum friction between parallel metallic slabs

    SciTech Connect (OSTI)

    Despoja, Vito

    2011-05-15

    We present a new derivation of the friction force between two metallic slabs moving with constant relative parallel velocity, based on T=0 quantum-field theory formalism. By including a fully nonlocal description of dynamically screened electron fluctuations in the slab, and avoiding the usual matching-condition procedure, we generalize previous expressions for the friction force, to which our results reduce in the local limit. Analyzing the friction force calculated in the two local models and in the nonlocal theory, we show that for physically relevant velocities local theories using the plasmon and Drude models of dielectric response are inappropriate to describe friction, which is due to excitation of low-energy electron-hole pairs, which are properly included in nonlocal theory. We also show that inclusion of dissipation in the nonlocal electronic response has negligible influence on friction.

  12. Seeing the Atomic Orbital: First-Principles Study of the Effect of Tip Termination on Atomic Force Microscopy

    E-Print Network [OSTI]

    Simons, Jack

    , University of Utah, Salt Lake City, Utah 84112, USA 2 Center for High Performance Computing, University

  13. Detection of slow atoms confined in a Cesium vapor cell by spatially separated pump and probe laser beams

    E-Print Network [OSTI]

    Todorov, Petko; Maurin, Isabelle; Saltiel, Solomon; Bloch, Daniel

    2013-01-01

    The velocity distribution of atoms in a thermal gas is usually described through a Maxwell-Boltzman distribution of energy, and assumes isotropy. As a consequence, the probability for an atom to leave the surface under an azimuth angle {\\theta} should evolve as cos {\\theta}, in spite of the fact that there is no microscopic basis to justify such a law. The contribution of atoms moving at a grazing incidence towards or from the surface, i.e. atoms with a small normal velocity, here called "slow" atoms, reveals essential in the development of spectroscopic methods probing a dilute atomic vapor in the vicinity of a surface, enabling a sub-Doppler resolution under a normal incidence irradiation. The probability for such "slow" atoms may be reduced by surface roughness and atom-surface interaction. Here, we describe a method to observe and to count these slow atoms relying on a mechanical discrimination, through spatially separated pump and probe beams. We also report on our experimental progresses toward such a g...

  14. Dislocation dynamics: from microscopic models to macroscopic crystal plasticity

    E-Print Network [OSTI]

    Hajj, A El; Monneau, R

    2009-01-01

    In this paper we study the connection between four models describing dislocation dynamics: a generalized 2D Frenkel-Kontorova model at the atomic level, the Peierls-Nabarro model, the discrete dislocation dynamics and a macroscopic model with dislocation densities. We show how each model can be deduced from the previous one at a smaller scale.

  15. Spectral Emission of Moving Atom

    E-Print Network [OSTI]

    J. X. Zheng-Johansson

    2008-03-17

    A renewed analysis of the H.E. Ives and G.R. Stilwell's experiment on moving hydrogen canal rays (J. Opt. Soc. Am., 1938, v.28, 215) concludes that the spectral emission of a moving atom exhibits always a redshift which informs not the direction of the atom's motion. The conclusion is also evident from a simple energy relation: atomic spectral radiation is emitted as an orbiting electron consumes a portion of its internal energy on transiting to a lower-energy state which however has in a moving atom an additional energy gain; this results in a redshift in the emission frequency. Based on auxiliary experimental information and a scheme for de Broglie particle formation, we give a vigorous elucidation of the mechanism for deceleration radiation of atomic electron; the corresponding prediction of the redshift is in complete agreement with the Ives and Stilwell's experimental formula.

  16. In-situ control system for atomization

    DOE Patents [OSTI]

    Anderson, I.E.; Figliola, R.S.; Terpstra, R.L.

    1995-06-13

    Melt atomizing apparatus comprising a melt supply orifice for supplying the melt for atomization and gas supply orifices proximate the melt supply orifice for supplying atomizing gas to atomize the melt as an atomization spray is disclosed. The apparatus includes a sensor, such as an optical and/or audio sensor, for providing atomization spray data, and a control unit responsive to the sensed atomization spray data for controlling at least one of the atomizing gas pressure and an actuator to adjust the relative position of the gas supply orifice and melt supply in a manner to achieve a desired atomization spray. 3 figs.

  17. Nuclear force in Lattice QCD

    E-Print Network [OSTI]

    T. T. Takahashi; T. Doi; H. Suganuma

    2006-01-05

    We perform the quenched lattice QCD analysis on the nuclear force (baryon-baryon interactions). We employ $20^3\\times 24$ lattice at $\\beta=5.7$ ($a\\simeq 0.19$ fm) with the standard gauge action and the Wilson quark action with the hopping parameters $\\kappa=0.1600, 0.1625, 0.1650$, and generate about 200 gauge configurations. We measure the temporal correlators of the two-baryon system which consists of heavy-light-light quarks. We extract the inter-baryon force as a function of the relative distance $r$. We also evaluate the contribution to the nuclear force from each ``Feynman diagram'' such as the quark-exchange diagram individually, and single out the roles of Pauli-blocking effects or quark exchanges in the inter-baryon interactions.

  18. Supersonic coal water slurry fuel atomizer

    DOE Patents [OSTI]

    Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA); Balsavich, John (Foxborough, MA)

    1991-01-01

    A supersonic coal water slurry atomizer utilizing supersonic gas velocities to atomize coal water slurry is provided wherein atomization occurs externally of the atomizer. The atomizer has a central tube defining a coal water slurry passageway surrounded by an annular sleeve defining an annular passageway for gas. A converging/diverging section is provided for accelerating gas in the annular passageway to supersonic velocities.

  19. Coherent control of light transport in a dense and disordered atomic ensemble

    E-Print Network [OSTI]

    A. S. Sheremet; D. F. Kornovan; L. V. Gerasimov; B. Gouraud; J. Laurat; D. V. Kupriyanov

    2015-03-09

    Light transport in a dense and disordered cold atomic ensemble, where the cooperation of atomic dipoles essentially modifies their coupling with the radiation modes, offers an alternative approach to light-matter interfacing protocols. Here, we show how the cooperativity and quasi-static dipole interaction affect the process of light propagation under the conditions of electromagnetically-induced transparency (EIT). We perform comparative analysis of the self-consistent approach with ab-initio microscopic calculations and emphasize the role of the interatomic interaction in the dipoles' dynamics. Our results show that in such a dense and strongly disordered system the EIT-based light storage protocol stays relatively insensitive to configuration variations and can be obtained with essentially less atoms than it is normally needed for dilute configurations.

  20. Automatic HTS force measurement instrument

    DOE Patents [OSTI]

    Sanders, S.T.; Niemann, R.C.

    1999-03-30

    A device is disclosed for measuring the levitation force of a high temperature superconductor sample with respect to a reference magnet includes a receptacle for holding several high temperature superconductor samples each cooled to superconducting temperature. A rotatable carousel successively locates a selected one of the high temperature superconductor samples in registry with the reference magnet. Mechanism varies the distance between one of the high temperature superconductor samples and the reference magnet, and a sensor measures levitation force of the sample as a function of the distance between the reference magnet and the sample. A method is also disclosed. 3 figs.

  1. Automatic HTS force measurement instrument

    DOE Patents [OSTI]

    Sanders, Scott T. (Valparaiso, IN); Niemann, Ralph C. (Downers Grove, IL)

    1999-01-01

    A device for measuring the levitation force of a high temperature superconductor sample with respect to a reference magnet includes a receptacle for holding several high temperature superconductor samples each cooled to superconducting temperature. A rotatable carousel successively locates a selected one of the high temperature superconductor samples in registry with the reference magnet. Mechanism varies the distance between one of the high temperature superconductor samples and the reference magnet, and a sensor measures levitation force of the sample as a function of the distance between the reference magnet and the sample. A method is also disclosed.

  2. Correlated density-dependent chiral forces for infinite matter calculations within the Green's function approach

    E-Print Network [OSTI]

    Arianna Carbone; Arnau Rios; Artur Polls

    2014-11-19

    The properties of symmetric nuclear and pure neutron matter are investigated within an extended self-consistent Green's function method that includes the effects of three-body forces. We use the ladder approximation for the study of infinite nuclear matter and incorporate the three-body interaction by means of a density-dependent two-body force. This force is obtained via a correlated average over the third particle, with an in-medium propagator consistent with the many-body calculation we perform. We analyze different prescriptions in the construction of the average and conclude that correlations provide small modifications at the level of the density-dependent force. Microscopic as well as bulk properties are studied, focusing on the changes introduced by the density dependent two-body force. The total energy of the system is obtained by means of a modified Galitskii-Migdal-Koltun sum rule. Our results validate previously used uncorrelated averages and extend the availability of chirally motivated forces to a larger density regime.

  3. Training program to prepare the U.S. DOE laboratories for the entry into force of the protocol additional to the agreement between the United States of America and the International Atomic Energy Agency for the application of safeguards in the United

    SciTech Connect (OSTI)

    Boyer, Brian David; Stevens, Rebecca C; Uribe, Eva C; Sandoval, M Analisa; Valente, John N; Valente, John U; Jo, Jae H; Sellen, Joana

    2009-01-01

    In 2008, a joint team from Brookhaven National Laboratory (BNL) and Los Alamos National Laboratory (LANL) consisting of specialists in training IAEA inspectors in the use of complementary access activities formulated a training program to prepare the U.S DOE laboratories for the entry into force of the U.S. Additional Protocol. Since the U.S. Additional Protocol would allow for IAEA access to the DOE laboratories under the aegis of complementary access activities, the DOE laboratories would need to prepare for such visits. The goal of the training was to ensure that the DOE laboratories would successfully host an IAEA complementary access. In doing so, the labs must be able to provide the IAEA with the information that the IAEA would need to resolve its questions about the U.S. Declaration and declared activities at the lab, and also protect certain equities, as provided under the U.S. Additional Protocol Article 1.b and c. which set forth a 'National Security Exclusion.' This 'NSE' states that the AP provisions apply within the United States 'excluding only instances where its application would result in access by the Agency to activities with direct national security significance to the United States or to location or information associated with such activities.' These activities are referred to collectively as DNSS-direct national security significance. Furthermore, the U.S. has a specific right to employ managed access, without prejudice to the right under Article 1.b, in connection with activities of DNSS. The provisions in Articles 1.b and 1.c are unique to the U.S. AP, and are additional to the more general right, under Article 7, to use managed access to protect from disclosure proprietary and/or proliferation-sensitive information, and to meet safety and security requirements, that is incorporated directly from the Model Additional Protocol. The BNL-LANL team performed training at Lawrence Livermore National Laboratory, Idaho National Laboratory, and Oak Ridge National Laboratory to cover the situations that these labs, which respectively represent nuclear weapons labs, nuclear energy labs, and science labs and environmental management sites, would encounter during a complementary access. Each of the three labs hosted a mock complementary access activity, which included mock inspectors from the BNL-LANL team. In addition to reviewing the draft declarations from each of the host labs, the BNL-LANL team conducted open source research in a manner similar to what IAEA inspectors would do to research the activities at a location and prepare questions for the location to answer and that would be the focus of a complementary access. The host labs and other labs attending the training found the training to be extremely useful and helpful in making sure that each lab's Additional Protocol team had made correct declarations of nuclear activities, had properly trained staff ready to host and answer IAEA inquiries, and would implement managed access during a complementary access that would provide access by the IAEA team to resolve questions or inconsistencies about a particular declaration and still protect the information addressed by Articles 1 and 7 of the U.S. AP.

  4. Work Force Planning for Public Power Utilities

    E-Print Network [OSTI]

    Work Force Planning for Public Power Utilities: Ensuring Resources to Meet Projected.............................................................................20 #12;ii Work Force Planning for Public Power Utilities #12;1 Work Force Planning for Public Power as a result of the aging work force; and · Public power utilities need to do more to plan for their future

  5. Solvent-induced forces in protein folding

    SciTech Connect (OSTI)

    Ben-Naim, A. (Hebrew Univ., Jerusalem (Israel))

    1990-08-23

    The solvent-induced forces between various groups on the protein are examined. It is found that the intramolecular hydrophilic forces are likely to be the strongest forces mediated through the solvent. It is argued that these are probably the most important solvent-induced driving forces in the process of protein folding.

  6. October 9, 2014- SEAB Task Force Meeting

    Broader source: Energy.gov [DOE]

    SECRETARY OF ENERGY ADVISORY BOARDTask Force Meeting on Technology Development for Environmental Management (EM)

  7. LABORATORY II FORCE AND CONSERVATION OF ENERGY

    E-Print Network [OSTI]

    Minnesota, University of

    on an object and its kinetic energy. · Define and use sine, cosine and tangent for a right triangleLABORATORY II FORCE AND CONSERVATION OF ENERGY Lab II - 1 After studying forces and material bodies the relationship between forces and energy conservation. Energy and forces, together, support an extremely

  8. Atomic Resolution Imaging and Quantification of Chemical Functionality of Surfaces

    SciTech Connect (OSTI)

    Schwarz, Udo

    2014-12-10

    The work carried out from 2006-2014 under DoE support was targeted at developing new approaches to the atomic-scale characterization of surfaces that include species-selective imaging and an ability to quantify chemical surface interactions with site-specific accuracy. The newly established methods were subsequently applied to gain insight into the local chemical interactions that govern the catalytic properties of model catalysts of interest to DoE. The foundation of our work was the development of three-dimensional atomic force microscopy (3D-AFM), a new measurement mode that allows the mapping of the complete surface force and energy fields with picometer resolution in space (x, y, and z) and piconewton/millielectron volts in force/energy. From this experimental platform, we further expanded by adding the simultaneous recording of tunneling current (3D-AFM/STM) using chemically well-defined tips. Through comparison with simulations, we were able to achieve precise quantification and assignment of local chemical interactions to exact positions within the lattice. During the course of the project, the novel techniques were applied to surface-oxidized copper, titanium dioxide, and silicon oxide. On these materials, defect-induced changes to the chemical surface reactivity and electronic charge density were characterized with site-specific accuracy.

  9. Ecosystem Task Force Meeting Minutes

    E-Print Network [OSTI]

    New Hampshire, University of

    targets for future reductions? 3.1. No. We could work on those with the Task Force. Water Quality. How would growth affect water quality? 3.1. Are we following Rob's recommendations from storm water. 5. There is more work to be done to characterize lands to east as well as west. Waste Management

  10. LABORATORY I FORCES AND EQUILIBRIUM

    E-Print Network [OSTI]

    Minnesota, University of

    LABORATORY I FORCES AND EQUILIBRIUM Lab I -1 In biological systems, most objects of interest system. OBJECTIVES: After successfully completing this laboratory, you should be able to: · Determine and 6), and chapter 15 (section 4). It is likely that you will be doing some of these laboratory

  11. Nuclear Force from String Theory

    E-Print Network [OSTI]

    Koji Hashimoto; Tadakatsu Sakai; Shigeki Sugimoto

    2010-03-09

    We compute nuclear force in a holographic model of QCD on the basis of a D4-D8 brane configuration in type IIA string theory. Repulsive core of nucleons is quite important in nuclear physics, but its origin has not been well-understood in strongly-coupled QCD. We find that string theory via gauge/string duality deduces this repulsive core at short distance between nucleons. Since baryons in the model are realized as solitons given by Yang-Mills instanton configuration on flavor D8-branes, ADHM construction of two instantons probes well the nucleon interaction at short scale, which provides the nuclear force quantitatively. We obtain, as well as a tensor force, a central force which is strongly repulsive as suggested in experiments and lattice results. In particular, the nucleon-nucleon potential V(r) (as a function of the distance) scales as 1/r^2, which is peculiar to the holographic model. We compare our results with one-boson exchange model using the nucleon-nucleon-meson coupling obtained in our previous paper (arXiv:0806.3122).

  12. Anticipating the atom: popular perceptions of atomic power before Hiroshima 

    E-Print Network [OSTI]

    d'Emal, Jacques-Andre Christian

    1994-01-01

    Before Hiroshima made the Bomb an object of popular concern, possible implications and applications of atomic physics had been discussed in the public forum. The new science of X-rays and radium promised the possibilities of unlimited energy...

  13. The Backbone Conformational Entropy of Protein Folding: Experimental Measures from Atomic

    E-Print Network [OSTI]

    Hansma, Paul

    The Backbone Conformational Entropy of Protein Folding: Experimental Measures from Atomic Force range of proteins.1 ­ 15 When applied to a protein comprised of multiple independent folding units of information regarding the mechanical properties, folding kinetics and thermodynamics of proteins, some

  14. Critique of the Centrifugal Effect in the Hydrogen Atom Frank Rioux

    E-Print Network [OSTI]

    Rioux, Frank

    Critique of the Centrifugal Effect in the Hydrogen Atom Frank Rioux Some quantum textbooks invoke with involves the middle term in the Hamiltonian given above. Some authors call it the centrifugal potential the effective potential energy. In support of this maneuver they invoke the idea of centrifugal force, which

  15. Analytical scanning evanescent microwave microscope and control stage

    DOE Patents [OSTI]

    Xiang, Xiao-Dong (Danville, CA); Gao, Chen (Anhui, CN); Duewer, Fred (Albany, CA); Yang, Hai Tao (Albany, CA); Lu, Yalin (Chelmsford, MA)

    2009-06-23

    A scanning evanescent microwave microscope (SEMM) that uses near-field evanescent electromagnetic waves to probe sample properties is disclosed. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from to microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enable quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials. The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling. The SEMM can be used to measure electrical properties of both dielectric and electrically conducting materials.

  16. Fully microscopic shell-model calculations with realistic effective hamiltonians

    E-Print Network [OSTI]

    L. Coraggio; A. Covello; A. Gargano; N. Itaco; T. T. S. Kuo

    2011-01-24

    The advent of nucleon-nucleon potentials derived from chiral perturbation theory, as well as the so-called V-low-k approach to the renormalization of the strong short-range repulsion contained in the potentials, have brought renewed interest in realistic shell-model calculations. Here we focus on calculations where a fully microscopic approach is adopted. No phenomenological input is needed in these calculations, because single-particle energies, matrix elements of the two-body interaction, and matrix elements of the electromagnetic multipole operators are derived theoretically. This has been done within the framework of the time-dependent degenerate linked-diagram perturbation theory. We present results for some nuclei in different mass regions. These evidence the ability of realistic effective hamiltonians to provide an accurate description of nuclear structure properties.

  17. Scanning optical microscope with long working distance objective

    DOE Patents [OSTI]

    Cloutier, Sylvain G. (Newark, DE)

    2010-10-19

    A scanning optical microscope, including: a light source to generate a beam of probe light; collimation optics to substantially collimate the probe beam; a probe-result beamsplitter; a long working-distance, infinity-corrected objective; scanning means to scan a beam spot of the focused probe beam on or within a sample; relay optics; and a detector. The collimation optics are disposed in the probe beam. The probe-result beamsplitter is arranged in the optical paths of the probe beam and the resultant light from the sample. The beamsplitter reflects the probe beam into the objective and transmits resultant light. The long working-distance, infinity-corrected objective is also arranged in the optical paths of the probe beam and the resultant light. It focuses the reflected probe beam onto the sample, and collects and substantially collimates the resultant light. The relay optics are arranged to relay the transmitted resultant light from the beamsplitter to the detector.

  18. Transmission electron microscope sample holder with optical features

    DOE Patents [OSTI]

    Milas, Mirko (Port Jefferson, NY); Zhu, Yimei (Stony Brook, NY); Rameau, Jonathan David (Coram, NY)

    2012-03-27

    A sample holder for holding a sample to be observed for research purposes, particularly in a transmission electron microscope (TEM), generally includes an external alignment part for directing a light beam in a predetermined beam direction, a sample holder body in optical communication with the external alignment part and a sample support member disposed at a distal end of the sample holder body opposite the external alignment part for holding a sample to be analyzed. The sample holder body defines an internal conduit for the light beam and the sample support member includes a light beam positioner for directing the light beam between the sample holder body and the sample held by the sample support member.

  19. Analytical scanning evanescent microwave microscope and control stage

    DOE Patents [OSTI]

    Xiang, Xiao-Dong; Gao, Chen; Duewer, Fred; Yang, Hai Tao; Lu, Yalin

    2013-01-22

    A scanning evanescent microwave microscope (SEMM) that uses near-field evanescent electromagnetic waves to probe sample properties is disclosed. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from to microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enable quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials. The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling. The SEMM can be used to measure electrical properties of both dielectric and electrically conducting materials.

  20. Microscopic return point memory in Co/Pd multilayer films

    SciTech Connect (OSTI)

    Seu, K.A.; Su, R.; Roy, S.; Parks, D.; Shipton, E.; Fullerton, E.E.; Kevan, S.D.

    2009-10-01

    We report soft x-ray speckle metrology measurements of microscopic return point and complementary point memory in Co/Pd magnetic films having perpendicular anisotropy. We observe that the domains assemble into a common labyrinth phase with a period that varies by nearly a factor of two between initial reversal and fields near saturation. Unlike previous studies of similar systems, the ability of the film to reproduce its domain structure after magnetic cycling through saturation varies from loop to loop, from position to position on the sample, and with the part of the speckle pattern used in the metrology measurements. We report the distribution of memory as a function of field and discuss these results in terms of the reversal process.

  1. Arbitrary axisymmetric steady streaming: Flow, force and propulsion

    E-Print Network [OSTI]

    Spelman, Tamsin A

    2015-01-01

    A well-developed method to induce mixing on microscopic scales is to exploit flows generated by steady streaming. Steady streaming is a classical fluid dynamics phenomenon whereby a time-periodic forcing in the bulk or along a boundary is enhanced by inertia to induce a non-zero net flow. Building on classical work for simple geometrical forcing and motivated by the complex shape oscillations of elastic capsules and bubbles, we develop the mathematical framework to quantify the steady streaming of a spherical body with arbitrary axisymmetric time-periodic boundary conditions. We compute the flow asymptotically for small-amplitude oscillations of the boundary in the limit where the viscous penetration length scale is much smaller than the body. In that case, the flow has a boundary layer structure and the fluid motion is solved by asymptotic matching. Our results, presented in the case of no-slip boundary conditions and extended to include the motion of vibrating free surfaces, recovers classical work as parti...

  2. Chemical factors influencing selenium atomization 

    E-Print Network [OSTI]

    Buren, Mary Sue

    1980-01-01

    Atomization. (August 1980) Mary Sue Buren, B, S. , Angelo State University Chairman of Advisory Comm1ttee: Dr. Thomas M. Vickrey Selenium in an acid1c matrix was analyzed using graphite furnace atom1c absorption with Zeeman-effect background correct1on.... Nickel(II} and lanthanum( III) were introduced as matrix modifiers to determine their effect on interferences 1n selenium atom1zation. In add1tion to matr1x mod1ficat1on, surface coating the graphite furnace with z1rconium and tantalum salts was also...

  3. Constraints on New Gravitylike Forces in the Nanometer Range

    E-Print Network [OSTI]

    Kamiya, Y; Tani, M; Kim, G N; Komamiya, S

    2015-01-01

    We report on a new constraint on gravitylike short-range forces, in which the interaction charge is mass, obtained by measuring the angular distribution of 5 A neutrons scattering off atomic xenon gas. Around 10^7 scattering events were collected at the 40 m small angle neutron scattering beam line located at the HANARO research reactor of the Korean Atomic Energy Research Institute. The extracted coupling strengths of new forces in the Yukawa-type parametrization are g^2 = (0.2 \\pm 6.8 \\pm 2.0) \\times 10^-15 GeV^2 and g^2 = (-5.3 \\pm 9.0 + 2.7 -2.8) \\times 10^-17 GeV^2 for interaction ranges of 0.1 and 1.0 nm, respectively. These strengths correspond to 95% confidence level limits of g^2 < (1.4 \\pm 0.2) \\times 10^-14 GeV^-2 and g^2 < (1.3 \\pm 0.2) \\times 10^-16 GeV^-2, improving the current limits for interaction ranges between 4 and 0.04 nm by a factor of up to 10.

  4. Constraints on New Gravitylike Forces in the Nanometer Range

    E-Print Network [OSTI]

    Y. Kamiya; K. Itagami; M. Tani; G. N. Kim; S. Komamiya

    2015-04-09

    We report on a new constraint on gravitylike short-range forces, in which the interaction charge is mass, obtained by measuring the angular distribution of 5 A neutrons scattering off atomic xenon gas. Around 10^7 scattering events were collected at the 40 m small angle neutron scattering beam line located at the HANARO research reactor of the Korean Atomic Energy Research Institute. The extracted coupling strengths of new forces in the Yukawa-type parametrization are g^2 = (0.2 \\pm 6.8 \\pm 2.0) \\times 10^-15 GeV^2 and g^2 = (-5.3 \\pm 9.0 + 2.7 -2.8) \\times 10^-17 GeV^2 for interaction ranges of 0.1 and 1.0 nm, respectively. These strengths correspond to 95% confidence level limits of g^2 < (1.4 \\pm 0.2) \\times 10^-14 GeV^-2 and g^2 < (1.3 \\pm 0.2) \\times 10^-16 GeV^-2, improving the current limits for interaction ranges between 4 and 0.04 nm by a factor of up to 10.

  5. Remote control of a scanning electron microscope aperture and gun alignment

    DOE Patents [OSTI]

    Cramer, Charles E.; Campchero, Robert J.

    2003-10-07

    This invention relates to a remote control system which through gear motors coupled to the scanning electron microscope (SEM) manual control knobs readily permits remote adjustments as necessary.

  6. EST-CE QU'ON VOlT ATRAVERS UN MICROSCOPE? '

    E-Print Network [OSTI]

    Aubin, David

    'aimable autonsatJon de1auteur etde Blackwell Publishing. EST-CE QU'ON VOlT ATRAVERS UN MICROSCOPE? 239 Les

  7. Gas-grain chemistry in cold interstellar cloud cores with a microscopic Monte Carlo approach to surface chemistry

    E-Print Network [OSTI]

    Q. Chang; H. M. Cuppen; E. Herbst

    2007-05-24

    AIM: We have recently developed a microscopic Monte Carlo approach to study surface chemistry on interstellar grains and the morphology of ice mantles. The method is designed to eliminate the problems inherent in the rate-equation formalism to surface chemistry. Here we report the first use of this method in a chemical model of cold interstellar cloud cores that includes both gas-phase and surface chemistry. The surface chemical network consists of a small number of diffusive reactions that can produce molecular oxygen, water, carbon dioxide, formaldehyde, methanol and assorted radicals. METHOD: The simulation is started by running a gas-phase model including accretion onto grains but no surface chemistry or evaporation. The starting surface consists of either flat or rough olivine. We introduce the surface chemistry of the three species H, O and CO in an iterative manner using our stochastic technique. Under the conditions of the simulation, only atomic hydrogen can evaporate to a significant extent. Although it has little effect on other gas-phase species, the evaporation of atomic hydrogen changes its gas-phase abundance, which in turn changes the flux of atomic hydrogen onto grains. The effect on the surface chemistry is treated until convergence occurs. We neglect all non-thermal desorptive processes. RESULTS: We determine the mantle abundances of assorted molecules as a function of time through 2x10^5 yr. Our method also allows determination of the abundance of each molecule in specific monolayers. The mantle results can be compared with observations of water, carbon dioxide, carbon monoxide, and methanol ices in the sources W33A and Elias 16. Other than a slight underproduction of mantle CO, our results are in very good agreement with observations.

  8. Imaging atoms in 3-D

    ScienceCinema (OSTI)

    Ercius, Peter

    2014-06-27

    Berkeley Lab's Peter Ercius discusses "Imaging atoms in 3-D" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas

  9. Imaging atoms in 3-D

    SciTech Connect (OSTI)

    Ercius, Peter

    2013-10-31

    Berkeley Lab's Peter Ercius discusses "Imaging atoms in 3-D" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas

  10. Theoretical studies of atomic transitions

    SciTech Connect (OSTI)

    Fischer, C.F.

    1990-10-01

    This paper discusses: lifetime of excited states; core-polarization studies; large relativistic calculations; Monte Carlo Hartree-Fock (MCHF) atomic structure package; and MCHF codes for the hypercube. (LSP)

  11. Efimov physics in cold atoms

    SciTech Connect (OSTI)

    Braaten, Eric . E-mail: braaten@mps.ohio-state.edu; Hammer, H.-W. . E-mail: hammer@itkp.uni-bonn.de

    2007-01-15

    Atoms with a large scattering length have universal low-energy properties that do not depend on the details of their structure or their interactions at short distances. In the 2-atom sector, the universal properties are familiar and depend only on the scattering length. In the 3-atom sector for identical bosons, the universal properties include the existence of a sequence of shallow triatomic molecules called Efimov trimers and log-periodic dependence of scattering observables on the energy and the scattering length. In this review, we summarize the universal results that are currently known. We also summarize the experimental information that is currently available with an emphasis on 3-atom loss processes.

  12. Efimov Physics in Cold Atoms

    E-Print Network [OSTI]

    Eric Braaten; H. -W. Hammer

    2006-12-05

    Atoms with a large scattering length have universal low-energy properties that do not depend on the details of their structure or their interactions at short distances. In the 2-atom sector, the universal properties are familiar and depend only on the scattering length. In the 3-atom sector for identical bosons, the universal properties include the existence of a sequence of shallow triatomic molecules called Efimov trimers and log-periodic dependence of scattering observables on the energy and the scattering length. In this review, we summarize the universal results that are currently known. We also summarize the experimental information that is currently available with an emphasis on 3-atom loss processes.

  13. Casimir force for absorbing media in an open quantum system framework: Scalar model

    SciTech Connect (OSTI)

    Lombardo, Fernando C.; Rubio Lopez, Adrian E.; Mazzitelli, Francisco D.

    2011-11-15

    In this article we compute the Casimir force between two finite-width mirrors at finite temperature, working in a simplified model in 1+1 dimensions. The mirrors, considered as dissipative media, are modeled by a continuous set of harmonic oscillators which in turn are coupled to an external environment at thermal equilibrium. The calculation of the Casimir force is performed in the framework of the theory of open quantum systems. It is shown that the Casimir interaction has two different contributions: the usual radiation pressure from the vacuum, which is obtained for ideal mirrors without dissipation or losses, and a Langevin force associated with the noise induced by the interaction between dielectric atoms in the slabs and the thermal bath. Both contributions to the Casimir force are needed in order to reproduce the analogous Lifshitz formula in 1+1 dimensions. We also discuss the relationship between the electromagnetic properties of the mirrors and the spectral density of the environment.

  14. Microscopic origin of quantum chaos in rotational damping

    SciTech Connect (OSTI)

    Matsuo, M.; Dossing, T.; Vigezzi, E.; Broglia, R.A. (Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto (Japan) The Niels Bohr Institute, University of Copenhagen (Denmark) Instituto Nazionale di Fisica Nucleare, Sezione di Milano, Milano (Italy) Departimento di Fisica dell'Universita di Milano, Milano (Italy))

    1993-05-03

    The rotational spectrum of [sup 168]Yb is calclated by diagonalizing different effective interactions within the basis of unperturbed rotational bands provided by the cranked shell model. A transition between order and chaos taking place in the energy region between 1 and 2 MeV above the yrast line is observed, associated with the onset of rotational damping. It can be related to the higher multipole components of the force acting among the unperturbed rotational bands.

  15. Moøller polarimetry with polarized atomic hydrogen at MESA

    SciTech Connect (OSTI)

    Bartolomé, P. Aguar; Aulenbacher, K.; Tyukin, V. [Institut für Kernphysik, Johannes Gutenberg-University, D-55099 Mainz (Germany)

    2013-11-07

    A new generation of parity violation (PV) electron scattering experiments are planned to be carried out at the Institut für Kernphysik in Mainz. These experiments will be performed at low energies of 100-200 MeV using the new accelerator MESA (Mainz Energy recovering Superconducting Accelerator). One of the main challenges of such experiments is to achieve an accuracy in beam polarization measurements that must be below 0.5%. This very high accuracy can be reached using polarized atomic hydrogen gas, stored in an ultra-cold magnetic trap, as the target for electron beam polarimetry based on Mo/ller scattering. Electron spin-polarized atomic hydrogen can be stored at high densities of 10{sup 16} cm{sup ?2}, over relatively long time periods, in a high magnetic field (8T) and at low temperatures (0.3K). The gradient force splits the ground state of the hydrogen into four states with different energies. Atoms in the low energy states are trapped in the strong magnetic field region whereas the high energy states are repelled and pumped away. The physics of ultra-cold atomic hydrogen in magnetic traps and the status of the Mainz Hydro-Mo/ller project will be presented.

  16. The Engineering of Optical Conservative Force

    E-Print Network [OSTI]

    Du, Junjie; Ding, Kun; Du, Guiqiang; Lin, Zhifang; Chan, C T; Ng, Jack

    2015-01-01

    Optical forces have been fruitfully applied in a broad variety of areas that not only span the traditional scientific fields such as physics, chemistry, and biology, but also in more applied fields. It is customary and useful to split the optical force into the (conservative) gradient force and the (non-conservative) scattering and absorption force. These forces are different in attributes. The ability to tailor them will open great potential in fundamental optics and practical applications. Here, we present an analytical and a numerical approach to calculate these forces, and, with these tools, we create a fairly general class of 2D conservative optical force field. In general, particles immersed in an optical force do not obey equilibrium statistical mechanics, making the analysis complicated. With conservative forces, these issues are resolved.

  17. BEAM TRANSPORT AND STORAGE WITH COLD NEUTRAL ATOMS AND MOLECULES

    SciTech Connect (OSTI)

    Walstrom, Peter L.

    2012-05-15

    A large class of cold neutral atoms and molecules is subject to magnetic field-gradient forces. In the presence of a field, hyperfine atomic states are split into several Zeeman levels. The slopes of these curves vs. field are the effective magnetic moments. By means of optical pumping in a field, Zeeman states of neutral lithium atoms and CaH molecules with effective magnetic moments of nearly {+-} one Bohr magneton can be selected. Particles in Zeeman states for which the energy increases with field are repelled by increasing fields; particles in states for which the energy decreases with field are attracted to increasing fields. For stable magnetic confinement, field-repelled states are required. Neutral-particle velocities in the present study are on the order of tens to hundreds of m/s and the magnetic fields needed for transport and injection are on the order of in the range of 0.01-1T. Many of the general concepts of charged-particle beam transport carry over into neutral particle spin-force optics, but with important differences. In general, the role of bending dipoles in charged particle optics is played by quadrupoles in neutral particle optics; the role of quadrupoles is played by sextupoles. The neutralparticle analog of charge-exchange injection into storage rings is the use of lasers to flip the state of particles from field-seeking to field-repelled. Preliminary tracking results for two neutral atom/molecule storage ring configurations are presented. It was found that orbit instabilities limit the confinment time in a racetrack-shaped ring with discrete magnetic elements with drift spaces between them; stable behavior was observed in a toroidal ring with a continuous sextupole field. An alternative concept using a linear sextupole or octupole channel with solenoids on the ends is presently being considered.

  18. Centrifugal force in Kerr geometry

    E-Print Network [OSTI]

    Sai Iyer; A R Prasanna

    1992-07-31

    We have obtained the correct expression for the centrifugal force acting on a particle at the equatorial circumference of a rotating body in the locally non-rotating frame of the Kerr geometry. Using this expression for the equilibrium of an element on the surface of a slowly rotating Maclaurin spheroid, we obtain the expression for the ellipticity (as discussed earlier by Abramowicz and Miller) and determine the radius at which the ellipticity is maximum.

  19. Construction of force measuring optical tweezers instrumentation and investigations of biophysical properties of bacterial adhesion organelles

    E-Print Network [OSTI]

    Andersson, Magnus

    2015-01-01

    Optical tweezers are a technique in which microscopic-sized particles, including living cells and bacteria, can be non-intrusively trapped with high accuracy solely using focused light. The technique has therefore become a powerful tool in the field of biophysics. Optical tweezers thereby provide outstanding manipulation possibilities of cells as well as semi-transparent materials, both non-invasively and non-destructively, in biological systems. In addition, optical tweezers can measure minute forces (Adhesive bacterial organelles, so called pili, mediate adhesion to host cells and are therefore crucial...

  20. Microscopic Aspects of Stretched Exponential Relaxation (SER) in Homogeneous Molecular and Network Glasses and Polymers

    E-Print Network [OSTI]

    J. C. Phillips

    2010-05-04

    Because the theory of SER is still a work in progress, the phenomenon itself can be said to be the oldest unsolved problem in science, as it started with Kohlrausch in 1847. Many electrical and optical phenomena exhibit SER with probe relaxation I(t) ~ exp[-(t/{\\tau}){\\beta}], with 0 equilibrium scaling exponent; its value, especially in glasses, is both practically useful and theoretically significant. The mathematical complexity of SER is such that rigorous derivations of this peculiar function were not achieved until the 1970's. The focus of much of the 1970's pioneering work was spatial relaxation of electronic charge, but SER is a universal phenomenon, and today atomic and molecular relaxation of glasses and deeply supercooled liquids provide the most reliable data. As the data base grew, the need for a quantitative theory increased; this need was finally met by the diffusion-to-traps topological model, which yields a remarkably simple expression for the shape parameter {\\beta}, given by d*/(d* + 2). At first sight this expression appears to be identical to d/(d + 2), where d is the actual spatial dimensionality, as originally derived. The original model, however, failed to explain much of the data base. Here the theme of earlier reviews, based on the observation that in the presence of short-range forces only d* = d = 3 is the actual spatial dimensionality, while for mixed short- and long-range forces, d* = fd = d/2, is applied to four new spectacular examples, where it turns out that SER is useful not only for purposes of quality control, but also for defining what is meant by a glass in novel contexts. (Please see full abstract in main text)

  1. Microwave probes Dipole Blockade and van der Waals Forces in a Cold Rydberg Gas

    E-Print Network [OSTI]

    R. Celistrino Teixeira; C. Hermann-Avigliano; Thanh Long Nguyen; T. Cantat-Moltrecht; Jean-Michel Raimond; S. Haroche; S. Gleyzes; M. Brune

    2015-02-14

    We show that microwave spectroscopy of a dense Rydberg gas trapped on a superconducting atom chip in the dipole blockade regime reveals directly the dipole-dipole many-body interaction energy spectrum. We use this method to investigate the expansion of the Rydberg cloud under the effect of repulsive van der Waals forces and the breakdown of the frozen gas approximation. This study opens a promising route for quantum simulation of many-body systems and quantum information transport in chains of strongly interacting Rydberg atoms.

  2. Microwave probes Dipole Blockade and van der Waals Forces in a Cold Rydberg Gas

    E-Print Network [OSTI]

    Teixeira, R Celistrino; Nguyen, Thanh Long; Cantat-Moltrecht, T; Raimond, Jean-Michel; Haroche, S; Gleyzes, S; Brune, M

    2015-01-01

    We show that microwave spectroscopy of a dense Rydberg gas trapped on a superconducting atom chip in the dipole blockade regime reveals directly the dipole-dipole many-body interaction energy spectrum. We use this method to investigate the expansion of the Rydberg cloud under the effect of repulsive van der Waals forces and the breakdown of the frozen gas approximation. This study opens a promising route for quantum simulation of many-body systems and quantum information transport in chains of strongly interacting Rydberg atoms.

  3. Quantitative in-situ scanning electron microscope pull-out experiments and molecular dynamics simulations of carbon nanotubes embedded in palladium

    SciTech Connect (OSTI)

    Hartmann, S., E-mail: steffen.hartmann@etit.tu-chemnitz.de; Blaudeck, T.; Hermann, S.; Wunderle, B. [Technische Universität Chemnitz, Reichenhainer Str. 70, 09126 Chemnitz (Germany); Hölck, O. [Technische Universität Chemnitz, Reichenhainer Str. 70, 09126 Chemnitz (Germany); Fraunhofer IZM Berlin, Gustav-Meyer-Allee 25, 13355 Berlin (Germany); Schulz, S. E.; Gessner, T. [Technische Universität Chemnitz, Reichenhainer Str. 70, 09126 Chemnitz (Germany); Fraunhofer ENAS Chemnitz, Technologie-Campus 3, 09126 Chemnitz (Germany)

    2014-04-14

    In this paper, we present our results of experimental and numerical pull-out tests on carbon nanotubes (CNTs) embedded in palladium. We prepared simple specimens by employing standard silicon wafers, physical vapor deposition of palladium and deposition of CNTs with a simple drop coating technique. An AFM cantilever with known stiffness connected to a nanomanipulation system was utilized inside a scanning electron microscope (SEM) as a force sensor to determine forces acting on a CNT during the pull-out process. SEM-images of the cantilever attached to a CNT have been evaluated for subsequent displacement steps with greyscale correlation to determine the cantilever deflection. We compare the experimentally obtained pull-out forces with values of numerical investigations by means of molecular dynamics and give interpretations for deviations according to material impurities or defects and their influence on the pull-out data. We find a very good agreement of force data from simulation and experiment, which is 17 nN and in the range of 10–61 nN, respectively. Our findings contribute to the ongoing research of the mechanical characterization of CNT-metal interfaces. This is of significant interest for the design of future mechanical sensors utilizing the intrinsic piezoresistive effect of CNTs or other future devices incorporating CNT-metal interfaces.

  4. Microscopic Mechanisms and Dynamics Simulations of S3/2) Reacting with Methane

    E-Print Network [OSTI]

    1 Microscopic Mechanisms and Dynamics Simulations of O+ (4 S3/2) Reacting with Methane Lipeng Sun: The reaction O+ (4 S3/2) + methane is studied as a benchmark for developing the theory of polymer erosion by O;2 Microscopic Mechanisms and Dynamics Simulations of O+ (4 S3/2) Reacting with Methane spacecraft,3 surprisingly

  5. AOML Keynotes July-August 2004 Students Discover Microscopic World of Marine Bacteria

    E-Print Network [OSTI]

    Goodwin, Kelly D.

    AOML Keynotes July-August 2004 Students Discover Microscopic World of Marine Bacteria AOML microbiologist Kelly Goodwin helped teach young girls about the invisible world of marine bacteria at a recent support the growth of marine bacteria, microscopic life forms living in the ocean. They were taught how

  6. Macroscopic traffic models from microscopic car-following models H. K. Lee,1

    E-Print Network [OSTI]

    Kim, Doochul

    Macroscopic traffic models from microscopic car-following models H. K. Lee,1 H.-W. Lee,2 and D. Kim microscopic car-following models via a coarse-graining procedure. The method is first demonstrated. The derivation is also extended to general car-following models. DOI: 10.1103/PhysRevE.64.056126 PACS number

  7. Oblique-incidence reflectivity difference microscope for label-free high-throughput detection of biochemical

    E-Print Network [OSTI]

    Zhu, Xiangdong

    Oblique-incidence reflectivity difference microscope for label-free high-throughput detection (OI-RD) microscope, a form of polarization-modulated imaging ellipsometer, for label on the polarizer­ compensator­sample­analyzer scheme and under the off-null condition, a polarization-modulated OI

  8. Microscopic studies of nonlocal spin dynamics and spin transport (invited)

    SciTech Connect (OSTI)

    Adur, Rohan; Du, Chunhui; Cardellino, Jeremy; Scozzaro, Nicolas; Wolfe, Christopher S.; Wang, Hailong; Herman, Michael; Bhallamudi, Vidya P.; Pelekhov, Denis V.; Yang, Fengyuan; Hammel, P. Chris

    2015-05-07

    Understanding the behavior of spins coupling across interfaces in the study of spin current generation and transport is a fundamental challenge that is important for spintronics applications. The transfer of spin angular momentum from a ferromagnet into an adjacent normal material as a consequence of the precession of the magnetization of the ferromagnet is a process known as spin pumping. We find that, in certain circumstances, the insertion of an intervening normal metal can enhance spin pumping between an excited ferromagnetic magnetization and a normal metal layer as a consequence of improved spin conductance matching. We have studied this using inverse spin Hall effect and enhanced damping measurements. Scanned probe magnetic resonance techniques are a complementary tool in this context offering high resolution magnetic resonance imaging, localized spin excitation, and direct measurement of spin lifetimes or damping. Localized magnetic resonance studies of size-dependent spin dynamics in the absence of lithographic confinement in both ferromagnets and paramagnets reveal the close relationship between spin transport and spin lifetime at microscopic length scales. Finally, detection of ferromagnetic resonance of a ferromagnetic film using the photoluminescence of nitrogen vacancy spins in neighboring nanodiamonds demonstrates long-range spin transport between insulating materials, indicating the complexity and generality of spin transport in diverse, spatially separated, material systems.

  9. Photocathode Optimization for a Dynamic Transmission Electron Microscope: Final Report

    SciTech Connect (OSTI)

    Ellis, P; Flom, Z; Heinselman, K; Nguyen, T; Tung, S; Haskell, R; Reed, B W; LaGrange, T

    2011-08-04

    The Dynamic Transmission Electron Microscope (DTEM) team at Harvey Mudd College has been sponsored by LLNL to design and build a test setup for optimizing the performance of the DTEM's electron source. Unlike a traditional TEM, the DTEM achieves much faster exposure times by using photoemission from a photocathode to produce electrons for imaging. The DTEM team's work is motivated by the need to improve the coherence and current density of the electron cloud produced by the electron gun in order to increase the image resolution and contrast achievable by DTEM. The photoemission test setup is nearly complete and the team will soon complete baseline tests of electron gun performance. The photoemission laser and high voltage power supply have been repaired; the optics path for relaying the laser to the photocathode has been finalized, assembled, and aligned; the internal setup of the vacuum chamber has been finalized and mostly implemented; and system control, synchronization, and data acquisition has been implemented in LabVIEW. Immediate future work includes determining a consistent alignment procedure to place the laser waist on the photocathode, and taking baseline performance measurements of the tantalum photocathode. Future research will examine the performance of the electron gun as a function of the photoemission laser profile, the photocathode material, and the geometry and voltages of the accelerating and focusing components in the electron gun. This report presents the team's progress and outlines the work that remains.

  10. Microscopic dissipation in a cohesionless granular jet impact

    E-Print Network [OSTI]

    Nicholas Guttenberg

    2012-03-29

    Sufficiently fine granular systems appear to exhibit continuum properties, though the precise continuum limit obtained can be vastly different depending on the particular system. We investigate the continuum limit of an unconfined, dense granular flow. To do this we use as a test system a two-dimensional dense cohesionless granular jet impinging upon a target. We simulate this via a timestep driven hard sphere method, and apply a mean-field theoretical approach to connect the macroscopic flow with the microscopic material parameters of the grains. We observe that the flow separates into a cone with an interior cone angle determined by the conservation of momentum and the dissipation of energy. From the cone angle we extract a dimensionless quantity $A-B$ that characterizes the flow. We find that this quantity depends both on whether or not a deadzone --- a stationary region near the target --- is present, and on the value of the coefficient of dynamic friction. We present a theory for the scaling of $A-B$ with the coefficient of friction that suggests that dissipation is primarily a perturbative effect in this flow, rather than the source of qualitatively different behavior.

  11. Development of a light force accelerometer

    E-Print Network [OSTI]

    Butts, David LaGrange

    2008-01-01

    In this work, the feasibility of a light force accelerometer was experimentally demonstrated. The light force accelerometer is an optical inertial sensor which uses focused laser light to levitate and trap glass microspheres ...

  12. Sudden transition from naked atom decay to dressed atom decay

    E-Print Network [OSTI]

    Wei Zhu; D. L. Zhou

    2015-07-09

    The studies on quantum open system play key roles not only in fundamental problems in quantum mechanics but also in quantum computing and information processes. Here we propose a scheme to use a one dimensional coupling cavity array (CCA) as an artificial electromagnetic environment of a two-level atom. For a finite length of CCA, we find that after a turning time the population of excited state deviates suddenly from the exponential decay. We show that physically this phenomena corresponds to a transition from a naked atom decay to a dressed state decay. We hope that our finding will promote the studies on quantum system with a finite size environment.

  13. Quantum Electrodynamics of Atomic Resonances

    E-Print Network [OSTI]

    Miguel Ballesteros; Jérémy Faupin; Jürg Fröhlich; Baptiste Schubnel

    2015-03-09

    A simple model of an atom interacting with the quantized electromagnetic field is studied. The atom has a finite mass $m$, finitely many excited states and an electric dipole moment, $\\vec{d}_0 = -\\lambda_{0} \\vec{d}$, where $\\| d^{i}\\| = 1,$ $ i=1,2,3,$ and $\\lambda_0$ is proportional to the elementary electric charge. The interaction of the atom with the radiation field is described with the help of the Ritz Hamiltonian, $-\\vec{d}_0\\cdot \\vec{E}$, where $\\vec{E}$ is the electric field, cut off at large frequencies. A mathematical study of the Lamb shift, the decay channels and the life times of the excited states of the atom is presented. It is rigorously proven that these quantities are analytic functions of the momentum $\\vec{p}$ of the atom and of the coupling constant $\\lambda_0$, provided $|\\vec{p}| maps' applied to a complex dilatation of the original Hamiltonian, which yields an algorithm for the calculation of resonance energies that converges super-exponentially fast.

  14. Nuclear Radiological Threat Task Force Established | National...

    National Nuclear Security Administration (NNSA)

    Radiological Threat Task Force Established | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing...

  15. RELATING CLIMATE FORCINGS AND CLIMATE RESPONSE

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    RELATING CLIMATE FORCINGS AND CLIMATE RESPONSE Stephen E. Schwartz Upton NY USA Bern, Switzerland change are tightly correlated. Forcing by GHGs only leads to extremely low climate sensitivity, well to rapid changes in forcings by stratospheric volcanic aerosols. Climate sensitivity is quite low, probably

  16. Atomic Layer DepositionAtomic Layer Deposition (ALD) Conformality in(ALD) Conformality in

    E-Print Network [OSTI]

    Rubloff, Gary W.

    Atomic Layer DepositionAtomic Layer Deposition (ALD) Conformality in(ALD) Conformality in Nanopores, removal of template, and subsequent TEM analysis. Significance Atomic layer deposition (ALD) is widely in Nanopores Intellectual merit While atomic layer deposition (ALD) enables unprecedented control of atomic

  17. Atomizing, continuous, water monitoring module

    DOE Patents [OSTI]

    Thompson, C.V.; Wise, M.B.

    1997-07-08

    A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid. 3 figs.

  18. Ramsey interferometry with ultracold atoms

    E-Print Network [OSTI]

    D. Seidel; J. G. Muga

    2006-02-02

    We examine the passage of ultracold two-level atoms through two separated laser fields for the nonresonant case. We show that implications of the atomic quantized motion change dramatically the behavior of the interference fringes compared to the semiclassical description of this optical Ramsey interferometer. Using two-channel recurrence relations we are able to express the double-laser scattering amplitudes by means of the single-laser ones and to give explicit analytical results. When considering slower and slower atoms, the transmission probability of the system changes considerably from an interference behavior to a regime where scattering resonances prevail. This may be understood in terms of different families of trajectories that dominate the overall transmission probability in the weak field or in the strong field limit.

  19. Atomizing, continuous, water monitoring module

    DOE Patents [OSTI]

    Thompson, Cyril V. (Knoxville, TN); Wise, Marcus B. (Kingston, TN)

    1997-01-01

    A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid.

  20. Hot atom chemistry and radiopharmaceuticals

    SciTech Connect (OSTI)

    Krohn, Kenneth A.; Moerlein, Stephen M.; Link, Jeanne M.; Welch, Michael J.

    2012-12-19

    The chemical products made in a cyclotron target are a combined result of the chemical effects of the nuclear transformation that made the radioactive atom and the bulk radiolysis in the target. This review uses some well-known examples to understand how hot atom chemistry explains the primary products from a nuclear reaction and then how radiation chemistry is exploited to set up the optimal product for radiosynthesis. It also addresses the chemical effects of nuclear decay. There are important principles that are common to hot atom chemistry and radiopharmaceutical chemistry. Both emphasize short-lived radionuclides and manipulation of high specific activity nuclides. Furthermore, they both rely on radiochromatographic separation for identification of no-carrieradded products.

  1. Structural Characterization of Micromechanical Properties in Asphalt Using Atomic Force Microscopy 

    E-Print Network [OSTI]

    Allen, Robert Grover

    2012-02-14

    of the study was based on nano-indentation experiments performed within a micro-grid of asphalt phases in order to determine micromechanical properties such as stiffness, adhesion and elastic/plastic behavior. The change in microstructure...

  2. Atomic force microscopy study of the growth and annealing of Ge islands on Si(100)

    E-Print Network [OSTI]

    Liu, Bing; Berrie, Cindy L.; Kitajima, Takeshi; Bright, John; Leone, Stephen R.

    2002-03-01

    "superdome" (named b y W i n . iams et a/ . 1 5 ) . Superdomes will not only consume most o f t h e supersaturation, but also the surrounding small coherent islands. 1 6 This complicates the interpretation of island d e n -sity and size distribution...

  3. Reactivity of Ozone with Solid Potassium Iodide Investigated by Atomic Force Microscopy

    E-Print Network [OSTI]

    Brown, Matthew A.

    2008-01-01

    92697 2. Molecular Foundry, Lawrence Berkeley Nationalwere performed at the Molecular Foundry, Lawrence Berkeley

  4. Parallel Atomic Force Microscopy and NMR Spectroscopy To Investigate Self-Assembled Protein-Nucleotide Aggregates

    E-Print Network [OSTI]

    Dellaire, Graham

    - tially be quite useful for a wide variety of systems, since it would allow for the linkage of mesoscale

  5. Focused ion beam modification of atomic force microscopy tips for near-field scanning optical microscopy

    E-Print Network [OSTI]

    Krogmeier, Jeffrey R.; Dunn, Robert C.

    2001-12-01

    fabri- cation process and the need for expensive FIB instrumenta- tion, but these impediments may be minimized as the fabri- cation techniques are refined. Since these tips share many of the physical characteristics of AFM probes, they should be capable... fabri- cation process and the need for expensive FIB instrumenta- tion, but these impediments may be minimized as the fabri- cation techniques are refined. Since these tips share many of the physical characteristics of AFM probes, they should be capable...

  6. Atomic Force Microscopy of Photosystem II and Its Unit Cell Clustering Quantitatively Delineate the Mesoscale

    E-Print Network [OSTI]

    Geissler, Phillip

    the Mesoscale Variability in Arabidopsis Thylakoids Bibiana Onoa1 , Anna R. Schneider2 , Matthew D. Brooks3 Quantitatively Delineate the Mesoscale Variability in Arabidopsis Thylakoids. PLoS ONE 9(7): e101470. doi:10

  7. Mode-synthesizing atomic force microscopy and mode-synthesizing sensing

    DOE Patents [OSTI]

    Passain, Ali; Thundat, Thomas George; Tetard, Laurene

    2014-07-22

    A method of analyzing a sample that includes applying a first set of energies at a first set of frequencies to a sample and applying, simultaneously with the applying the first set of energies, a second set of energies at a second set of frequencies, wherein the first set of energies and the second set of energies form a multi-mode coupling. The method further includes detecting an effect of the multi-mode coupling.

  8. Investigations into Protein-Surface Interactions via Atomic Force Microscopy and Surface Plasmon Resonance

    E-Print Network [OSTI]

    Settle, Jenifer Kaye

    2012-08-31

    performed via surface plasmon resonance (SPR) to investigate the dynamics of this adsorption process on gold, and an amine-, carboxyl-, methyl- and hydroxyl-terminated SAM films. Chapter 4 provides background and investigation into F1-Adenosine triphosphate...

  9. Reactivity of Ozone with Solid Potassium Iodide Investigated by Atomic Force Microscopy

    E-Print Network [OSTI]

    Brown, Matthew A.

    2008-01-01

    J. C. , Reactivity of ozone on solid potassium iodide.and mechanisms of aqueous ozone reactions with bromide,for Dry Deposition of Ozone to Seawater Surfaces. Journal of

  10. Imaging of single hairpin ribozymes in solution by atomic force microscopy

    E-Print Network [OSTI]

    Walter, Nils G.

    and Molecular Genetics, The University of Vermont, Burlington, Vermont 05405, USA ABSTRACT The hairpin ribozyme, The University of Vermont, Burlington, Vermont 05405, USA; email: John+Burke

  11. The Cellular Mechanoresponse: Single-Cell Studies by Atomic Force Microscopy

    E-Print Network [OSTI]

    Crow, Alexis Kohnstamm

    2011-01-01

    L. (2008). Life and times of a cellular bleb. Biophys J 94,2007). Self?assembled cellular microarrays patterned usingand Ingber, D.  E. (2006). Cellular adaptation to mechanical

  12. Mechanical Signaling Induced Cellular Remodeling Studied By Integrated Optical And Atomic Force Microscopy 

    E-Print Network [OSTI]

    Sreenivasappa, Harini Bytaraya

    2014-12-08

    Vascular wall composition and mechanics are important for cardiovascular physiology and pathology. The reciprocal interaction between cells and their microenvironment influence cellular adaptation to external mechanical cues through the remodeling...

  13. Integrated Atomic Force Microscopy Techniques for Analysis of Biomaterials : : Study of Membrane Proteins

    E-Print Network [OSTI]

    Connelly, Laura S.

    2014-01-01

    TECHNIQUES FOR ANALYSIS OF BIOMATERIALS: STUDY OF MEMBRANETECHNIQUES FOR ANALYSIS OF BIOMATERIALS: STUDY OF MEMBRANE

  14. Applications of Atomic Force Microscopy in Biophysical Chemistry of Cells Valentin Lulevich,

    E-Print Network [OSTI]

    Liu, Gang-yu

    Lulevich, Fu-tong Liu, and Gang-yu Liu*, Department of Chemistry, UniVersity of California, DaVis, DaVis, California 95616, and Department of Dermatology, UniVersity of California at DaVis, Sacramento, California in all living cells and involves transport of intracellular products to the exterior of cells.6 Although

  15. Probing Nanotribological and Electrical Properties of Organic Molecular Films with Atomic Force Microscopy

    E-Print Network [OSTI]

    Weeks, Eric R.

    Graduate Group, University of California, Berkeley, California 3 Materials Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California Summary: Structural aspects between na- nomechanical and charge transport properties of molecular films at the molecular scale

  16. Near-Grazing Dynamics in Tapping-Mode Atomic Force Harry Dankowicza

    E-Print Network [OSTI]

    Zhao, Xiaopeng

    bifurcations, discontinuity mappings. 1 Introduction Nanostructured materials and devices can be endowed as hydrogen storage devices. Similarly, self-assembly of ferromag- netic nanoparticles is a promising technique for producing high-density magnetic data storage devices and biomedical materials with desirable

  17. Customized atomic force microscopy probe by focused-ion-beam-assisted tip

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnect Collidertransfer (Journal Article) | SciTech Connect Customized

  18. Average-Atom Thomson Scattering

    E-Print Network [OSTI]

    Johnson, Walter R.

    -Atom Approximation W. R. Johnson, Notre Dame J. Nilsen & K. T. Cheng, LLNL The cross section for Thomson scattering Average-Atom Model Divide plasma into WS cells with a nucleus and Z electrons p2 2 - Z r + V a(r) = a a(r) V(r) = VKS(n(r), r) n(r) = nb(r) + nc(r) 4r2nb(r) = nl 2(2l+1) 1+exp[( nl -µ)/kBT] Pnl(r)2 Z = r

  19. Macro- and microscopic properties of strontium doped indium oxide

    SciTech Connect (OSTI)

    Nikolaenko, Y. M.; Kuzovlev, Y. E.; Medvedev, Y. V.; Mezin, N. I.; Fasel, C.; Gurlo, A.; Schlicker, L.; Bayer, T. J. M.; Genenko, Y. A.

    2014-07-28

    Solid state synthesis and physical mechanisms of electrical conductivity variation in polycrystalline, strontium doped indium oxide In{sub 2}O{sub 3}:(SrO){sub x} were investigated for materials with different doping levels at different temperatures (T?=?20–300?°C) and ambient atmosphere content including humidity and low pressure. Gas sensing ability of these compounds as well as the sample resistance appeared to increase by 4 and 8 orders of the magnitude, respectively, with the doping level increase from zero up to x?=?10%. The conductance variation due to doping is explained by two mechanisms: acceptor-like electrical activity of Sr as a point defect and appearance of an additional phase of SrIn{sub 2}O{sub 4}. An unusual property of high level (x?=?10%) doped samples is a possibility of extraordinarily large and fast oxygen exchange with ambient atmosphere at not very high temperatures (100–200?°C). This peculiarity is explained by friable structure of crystallite surface. Friable structure provides relatively fast transition of samples from high to low resistive state at the expense of high conductance of the near surface layer of the grains. Microscopic study of the electro-diffusion process at the surface of oxygen deficient samples allowed estimation of the diffusion coefficient of oxygen vacancies in the friable surface layer at room temperature as 3?×?10{sup ?13}?cm{sup 2}/s, which is by one order of the magnitude smaller than that known for amorphous indium oxide films.

  20. Micromechanism linear actuator with capillary force sealing

    DOE Patents [OSTI]

    Sniegowski, Jeffry J. (Albuquerque, NM)

    1997-01-01

    A class of micromachine linear actuators whose function is based on gas driven pistons in which capillary forces are used to seal the gas behind the piston. The capillary forces also increase the amount of force transmitted from the gas pressure to the piston. In a major subclass of such devices, the gas bubble is produced by thermal vaporization of a working fluid. Because of their dependence on capillary forces for sealing, such devices are only practical on the sub-mm size scale, but in that regime they produce very large force times distance (total work) values.

  1. Lorentz-Force Hydrophone Characterization

    E-Print Network [OSTI]

    Grasland-Mongrain, Pol; Gilles, Bruno; Poizat, Adrien; Chapelon, Jean-Yves; Lafon, Cyril

    2014-01-01

    A Lorentz-force hydrophone consists of a thin wire placed inside a magnetic field. When under the influence of an ultrasound pulse, the wire vibrates and an electrical signal is induced by the Lorentz force that is proportional to the pulse amplitude. In this study a compact prototype of such a hydrophone is introduced and characterized, and the hydrodynamic model previously developed is refined. It is shown that the wire tension has a negligible effect on the measurement of pressure. The frequency response of the hydrophone reaches 1 MHz for wires with a diameter ranging between 70 and 400 \\micro m. The hydrophone exhibits a directional response such that the signal amplitude differs by less than 3dB as the angle of the incident ultrasound pulse varies from -20$^o$ and +20$^o$. The linearity of the measured signal is confirmed across the 50 kPa to 10 MPa pressure range, and an excellent resistance to cavitation is observed. This hydrophone is of interest for high pressure ultrasound measurements including Hi...

  2. Direct measurement of thermophoretic forces

    E-Print Network [OSTI]

    Laurent Helden; Ralf Eichhorn; Clemens Bechinger

    2014-12-19

    We study the thermophoretic motion of a micron sized single colloidal particle in front of a flat wall by evanescent light scattering. To quantify thermophoretic effects we analyse the nonequilibrium steady state (NESS) of the particle in a constant temperature gradient perpendicular to the confining walls. We propose to determine thermophoretic forces from a 'generalized potential' associated with the probability distribution of the particle position in the NESS. Experimentally we demonstrate, how this spatial probability distribution is measured and how thermophoretic forces can be extracted with 10 fN resolution. By varying temperature gradient and ambient temperature, the temperature dependence of Soret coefficient $S_T(T)$ is determined for $r = 2.5 \\mu m$ polystyrene and $r = 1.35 \\mu m$ melamine particles. The functional form of $S_T(T)$ is in good agreement with findings for smaller colloids. In addition, we measure and discuss hydrodynamic effects in the confined geometry. The theoretical and experimental technique proposed here extends thermophoresis measurements to so far inaccessible particle sizes and particle solvent combinations.

  3. Static balance control and external force estimation using ground reaction forces

    E-Print Network [OSTI]

    Ito, Satoshi

    Static balance control and external force estimation using ground reaction forces Satoshi ITO1 In this paper, we consider a balance control with focus- ing on ground reaction forces. As an example of balance control, the static balance with constant external forces act- ing is treated. Ankle joint torque is used

  4. Heterogeneous Force Chains in Cellularized Biopolymer Network

    E-Print Network [OSTI]

    Long Liang; Christopher Jones; Bo Sun; Yang Jiao

    2015-08-18

    Biopolymer Networks play an important role in coordinating and regulating collective cellular dynamics via a number of signaling pathways. Here, we investigate the mechanical response of a model biopolymer network due to the active contraction of embedded cells. Specifically, a graph (bond-node) model derived from confocal microscopy data is used to represent the network microstructure, and cell contraction is modeled by applying correlated displacements at specific nodes, representing the focal adhesion sites. A force-based stochastic relaxation method is employed to obtain force-balanced network under cell contraction. We find that the majority of the forces are carried by a small number of heterogeneous force chains emitted from the contracting cells. The force chains consist of fiber segments that either possess a high degree of alignment before cell contraction or are aligned due to the reorientation induced by cell contraction. Large fluctuations of the forces along different force chains are observed. Importantly, the decay of the forces along the force chains is significantly slower than the decay of radially averaged forces in the system. These results suggest that the fibrous nature of biopolymer network structure can support long-range force transmission and thus, long-range mechanical signaling between cells.

  5. Heterogeneous Force Chains in Cellularized Biopolymer Network

    E-Print Network [OSTI]

    Liang, Long; Sun, Bo; Jiao, Yang

    2015-01-01

    Biopolymer Networks play an important role in coordinating and regulating collective cellular dynamics via a number of signaling pathways. Here, we investigate the mechanical response of a model biopolymer network due to the active contraction of embedded cells. Specifically, a graph (bond-node) model derived from confocal microscopy data is used to represent the network microstructure, and cell contraction is modeled by applying correlated displacements at specific nodes, representing the focal adhesion sites. A force-based stochastic relaxation method is employed to obtain force-balanced network under cell contraction. We find that the majority of the forces are carried by a small number of heterogeneous force chains emitted from the contracting cells. The force chains consist of fiber segments that either possess a high degree of alignment before cell contraction or are aligned due to the reorientation induced by cell contraction. Large fluctuations of the forces along different force chains are observed. ...

  6. 1/27/2014 Microscopic Wind Turbines Offer Renewable Energyon the Go http://oilprice.com/Latest-Energy-News/World-News/Microscopic-Wind-Turbines-Offer-Renewable-Energy-on-the-Go.html 1/3

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    -Energy-News/World-News/Microscopic-Wind-Turbines-Offer-Renewable-Energy-on-the-Go.html 1/3 Log In Sign Up Energy on the Go Microscopic Wind Turbines Offer Renewable Energy on the Go By Brian Westenhaus | Thu, 23;1/27/2014 Microscopic Wind Turbines Offer Renewable Energyon the Go http://oilprice.com/Latest-Energy-News/World-News

  7. Atomic CP-violating polarizability

    E-Print Network [OSTI]

    Ravaine, B; Derevianko, A; Ravaine, Boris; Derevianko, Andrei

    2005-01-01

    Searches for CP violating effects in atoms and molecules provide important constrains on competing extensions to the standard model of elementary particles. In particular, CP violation in an atom leads to the CP-odd (T,P-odd) polarizability $\\beta^\\mathrm{CP}$: a magnetic moment $\\mu^\\mathrm{CP}$ is induced by an electric field $\\mathcal{E}_0$ applied to an atom, $\\mu^\\mathrm{CP} = \\beta^\\mathrm{CP} \\mathcal{E}_0 $. We estimate the CP-violating polarizability for rare-gas (diamagnetic) atoms He through Rn. We relate betaCP to the permanent electric dipole moment (EDM) of the electron and to the scalar constant of the CP-odd electron-nucleus interaction. The analysis is carried out using the third-order perturbation theory and the Dirac-Hartree-Fock formalism. We find that, as a function of nuclear charge Z, betaCP scales steeply as Z^5 R(Z), where slowly-varying R(Z) is a relativistic enhancement factor. Finally, we evaluate a feasibility of setting a limit on electron EDM by measuring CP-violating magnetizat...

  8. Demonstration of achromatic cold-neutron microscope utilizing axisymmetric focusing mirrors

    SciTech Connect (OSTI)

    Liu, D.; Khaykovich, B. [Nuclear Reactor Laboratory, Massachusetts Institute of Technology, 138 Albany St., Cambridge, Massachusetts 02139 (United States)] [Nuclear Reactor Laboratory, Massachusetts Institute of Technology, 138 Albany St., Cambridge, Massachusetts 02139 (United States); Hussey, D.; Jacobson, D.; Arif, M. [Physical Measurement Laboratory, NIST, Gaithersburg, Maryland 20899-8461 (United States)] [Physical Measurement Laboratory, NIST, Gaithersburg, Maryland 20899-8461 (United States); Gubarev, M. V.; Ramsey, B. D. [Marshall Space Flight Center, NASA, VP62, Huntsville, Alabama 35812 (United States)] [Marshall Space Flight Center, NASA, VP62, Huntsville, Alabama 35812 (United States); Moncton, D. E. [Nuclear Reactor Laboratory, Massachusetts Institute of Technology, 138 Albany St., Cambridge, Massachusetts 02139 (United States) [Nuclear Reactor Laboratory, Massachusetts Institute of Technology, 138 Albany St., Cambridge, Massachusetts 02139 (United States); Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States)

    2013-05-06

    An achromatic cold-neutron microscope with magnification 4 is demonstrated. The image-forming optics is composed of nested coaxial mirrors of full figures of revolution, so-called Wolter optics. The spatial resolution, field of view, and depth of focus are measured and found consistent with ray-tracing simulations. Methods of increasing the resolution and magnification are discussed, as well as the scientific case for the neutron microscope. In contrast to traditional pinhole-camera neutron imaging, the resolution of the microscope is determined by the mirrors rather than by the collimation of the beam, leading to possible dramatic improvements in the signal rate and resolution.

  9. Achieving atomic resolution magnetic dichroism by controlling the phase symmetry of an electron probe

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rusz, Jan; Idrobo, Juan -Carlos; Bhowmick, Somnath

    2014-09-30

    The calculations presented here reveal that an electron probe carrying orbital angular momentum is just a particular case of a wider class of electron beams that can be used to measure electron magnetic circular dichroism (EMCD) with atomic resolution. It is possible to obtain an EMCD signal with atomic resolution by simply breaking the symmetry of the electron probe phase front using the aberration-corrected optics of an scanning transmission electron microscope. The phase distribution of the probe depends on the magnetic symmetry and crystal structure of the sample. The calculations indicate that EMCD signals utilizing the phase of the electronmore »probe are as strong as those obtained by nanodiffraction methods.« less

  10. Understanding glass-forming ability through sluggish crystallization of atomically thin metallic glassy films

    SciTech Connect (OSTI)

    Sun, Y. T.; Cao, C. R.; Huang, K. Q.; Zhao, N. J.; Gu, L., E-mail: l.gu@iphy.ac.cn, E-mail: dzheng@iphy.ac.cn, E-mail: whw@iphy.ac.cn; Zheng, D. N., E-mail: l.gu@iphy.ac.cn, E-mail: dzheng@iphy.ac.cn, E-mail: whw@iphy.ac.cn; Wang, W. H., E-mail: l.gu@iphy.ac.cn, E-mail: dzheng@iphy.ac.cn, E-mail: whw@iphy.ac.cn [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-08-04

    The glass-forming ability (GFA) of an alloy, closely related to its ability to resist crystallization, is a crucial issue in condensed matter physics. So far, the studies on GFA are mostly statistical and empirical guides. Benefiting from the ultrahigh thermal stability of ultrathin metallic glassy film and high resolution spherical aberration-corrected transmission electron microscope, the crystallization of atomically thin ZrCu and its microalloyed ZrCuAl glasses with markedly different GFA was investigated at the atomic scale. We find the Zr diffusivity estimated from the density of nuclei is dramatically decreased by adding of Al, which is the major reason for the much better GFA of the ZrCuAl metallic glass.

  11. Atomic parity nonconservation and neutron radii in cesium isotopes

    E-Print Network [OSTI]

    B. Q. Chen; P. Vogel

    1993-03-05

    The interpretation of future precise experiments on atomic parity violation in terms of parameters of the Standard Model could be hampered by uncertainties in the atomic and nuclear structure. While the former can be overcome by measurement in a series of isotopes, the nuclear structure requires knowledge of the neutron density. We use the nuclear Hartree-Fock method, which includes deformation effects, to calculate the proton and neutron densities in {125}Cs-{139}Cs. We argue that the good agreement with the experimental charge radii, binding energies, and ground state spins signifies that the phenomenological nuclear force and the method of calculation that we use is adequate. Based on this agreement, and on calculations involving different effective interactions, we estimate the uncertainties in the differences of the neutron radii delta_{N,N'} and conclude that they cause uncertainties in the ratio of weak charges, the quantities determined in the atomic parity nonconservation experiments, of less than 10^{-3}. Such an uncertainty is smaller than the anticipated experimental error.

  12. Dark Forces At The Tevatron

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Buckley, Matt; Fileviez Perez, Pavel; Hooper, Dan; Neil, Ethan

    2011-08-19

    A simple explanation of the W + dijet excess recently reported by the CDF collaboration involves the introduction of a new gauge boson with sizable couplings to quarks, but with no or highly suppressed couplings to leptons. Anomaly-free theories which include such a leptophobic gauge boson must also include additional particle content, which may include a stable and otherwise viable candidate for dark matter. Based on the couplings and mass of the Z` required to generate the CDF excess, we predict such a dark matter candidate to possess an elastic scattering cross section with nucleons on the order of ?more »~ 10-40 cm2, providing a natural explanation for the signals reported by the CoGeNT and DAMA/LIBRA collaborations. In this light, CDF may be observing the gauge boson responsible for the force which mediates the interactions between the dark and visible matter of our universe.« less

  13. Nuclear Force from Lattice QCD

    E-Print Network [OSTI]

    N. Ishii; S. Aoki; T. Hatsuda

    2007-06-26

    Nucleon-nucleon (NN) potential is studied by lattice QCD simulations in the quenched approximation, using the plaquette gauge action and the Wilson quark action on a 32^4 (\\simeq (4.4 fm)^4) lattice. A NN potential V_{NN}(r) is defined from the equal-time Bethe-Salpeter amplitude with a local interpolating operator for the nucleon. By studying the NN interaction in the ^1S_0 and ^3S_1 channels, we show that the central part of V_{NN}(r) has a strong repulsive core of a few hundred MeV at short distances (r \\alt 0.5 fm) surrounded by an attractive well at medium and long distances. These features are consistent with the known phenomenological features of the nuclear force.

  14. Accessing Your EM Data Through the File Server A major problem of putting flash drives directly into the microscope

    E-Print Network [OSTI]

    Baker, Timothy S.

    into the microscope computer is the threat of viruses. A particularly malevolent virus could shut the microscope down including your home computer. Here are the steps for transferring and accessing your files. 1. On the microscope computer go to the Desktop and then to: My Computer/Tools/M ap Network Drive. 2. In the Drive: box

  15. The scanning electron microscope as an accelerator for the undergraduate advanced physics laboratory

    E-Print Network [OSTI]

    Peterson, Randolph S.

    Few universities or colleges have an accelerator for use with advanced physics laboratories, but many of these institutions have a scanning electron microscope (SEM) on site, often in the biology department. As an accelerator ...

  16. Automation of Challenging Spatial-Temporal Biomedical Observations With the Adaptive Scanning Optical Microscope (ASOM)

    E-Print Network [OSTI]

    Potsaid, Benjamin M.

    Biological studies, drug discovery, and medical diagnostics benefit greatly from automated microscope platforms that can outperform even the most skilled human operators in certain tasks. However, the small field-of-view ...

  17. Microscopic description of isoscalar giant resonance excitations in ??Ca and ¹¹?SN nuclei 

    E-Print Network [OSTI]

    Karki, Bhishma

    2000-01-01

    This thesis presents a microscopic description of isoscalar giant resonance excitations in ??Ca and ¹¹? Sn nuclei within the self-consistent Skyrme-Hartree-Fock-Random-Phase-Approximation (HF-RPA) theory. Such characteristic features...

  18. A Novel Method for Passive Digital Image Acquisition from a Scanning Electron Microscope

    E-Print Network [OSTI]

    Makarewicz, Joseph Sylvester

    2009-01-01

    The Center for Nanotechnology at NASA Ames Research Center is developing a microcolumn scanning electron microscope with energy-dispersive x-ray spectroscopy (MSEMS). The MSEMS has the potential for space explorations because it is lightweight, low...

  19. Atomic vapor laser isotope separation process

    DOE Patents [OSTI]

    Wyeth, R.W.; Paisner, J.A.; Story, T.

    1990-08-21

    A laser spectroscopy system is utilized in an atomic vapor laser isotope separation process. The system determines spectral components of an atomic vapor utilizing a laser heterodyne technique. 23 figs.

  20. Casimir force between integrable and chaotic pistons

    SciTech Connect (OSTI)

    Alvarez, Ezequiel; Mazzitelli, Francisco D.; Wisniacki, Diego A. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires, and Instituto de Fisica de Buenos Aires, Concejo Nacional de Investigaciones Cientificas y Tecnicas, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires (Argentina); Monastra, Alejandro G. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Concejo Nacional de Investigaciones Cientificas y Tecnicas, Avenida General Paz 1499, 1650 San Martin (Argentina)

    2010-11-15

    We have computed numerically the Casimir force between two identical pistons inside a very long cylinder, considering different shapes for the pistons. The pistons can be considered quantum billiards, whose spectrum determines the vacuum force. The smooth part of the spectrum fixes the force at short distances and depends only on geometric quantities like the area or perimeter of the piston. However, correcting terms to the force, coming from the oscillating part of the spectrum which is related to the classical dynamics of the billiard, could be qualitatively different for classically integrable or chaotic systems. We have performed a detailed numerical analysis of the corresponding Casimir force for pistons with regular and chaotic classical dynamics. For a family of stadium billiards, we have found that the correcting part of the Casimir force presents a sudden change in the transition from regular to chaotic geometries. This suggests that there could be signatures of quantum chaos in the Casimir effect.

  1. Low energy ($p,?$) reactions in Ni and Cu nuclei using microscopic optical model

    E-Print Network [OSTI]

    G. Gangopadhyay

    2010-08-05

    Radiative capture reactions for low energy protons have been theoretically studied for Ni and Cu isotopes using the microscopic optical model. The optical potential has been obtained in the folding model using different microscopic interactions with the nuclear densities from Relativistic Mean Field calculations. The calculated total cross sections as well as the cross sections for individually low lying levels have been compared with measurements involving stable nuclear targets. Rates for the rapid proton capture process have been evaluated for astrophysically important reactions.

  2. Towards a high-precision atomic gyroscope

    E-Print Network [OSTI]

    Van Camp, Mackenzie A. (Mackenzie Anne)

    2013-01-01

    In this thesis, I report on the design and construction of the Rubidium Atomic Gyroscope Experiment (RAGE) at Draper Lab.

  3. Forces on laboratory model dredge cutterhead 

    E-Print Network [OSTI]

    Young, Dustin Ray

    2010-07-14

    coefficients (non-cavitating) - D, z = water depth ft d1, d2 = Cutting force coefficients (cavitating) - d50 = Mean grain diameter mm Dc = Depth of Cut in Dcutter = Diameter of cutterhead in ????1???? = Distance between cell1 to center of mass... redesigned cell1 to center of mass of cutter in z direction in ? = Phase shift rad ?c = Cavitation transition angle rad ???? = Axial cutting force lb ??? = Horizontal cutting force (F#nc represents non-cavitating) lb ???? = Vertical cutting...

  4. QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS...

    Office of Scientific and Technical Information (OSTI)

    of model atoms in fields Milonni, P.W. 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; OPTICAL MODELS; QUANTUM MECHANICS;...

  5. Atomic vapor laser isotope separation

    SciTech Connect (OSTI)

    Stern, R.C.; Paisner, J.A.

    1985-11-08

    Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements.

  6. A 350 mK, 9 T scanning tunneling microscope for the study of superconducting thin films on insulating substrates and single crystals

    SciTech Connect (OSTI)

    Kamlapure, Anand; Saraswat, Garima; Ganguli, Somesh Chandra; Bagwe, Vivas; Raychaudhuri, Pratap; Pai, Subash P.

    2013-12-15

    We report the construction and performance of a low temperature, high field scanning tunneling microscope (STM) operating down to 350 mK and in magnetic fields up to 9 T, with thin film deposition and in situ single crystal cleaving capabilities. The main focus lies on the simple design of STM head and a sample holder design that allows us to get spectroscopic data on superconducting thin films grown in situ on insulating substrates. Other design details on sample transport, sample preparation chamber, and vibration isolation schemes are also described. We demonstrate the capability of our instrument through the atomic resolution imaging and spectroscopy on NbSe{sub 2} single crystal and spectroscopic maps obtained on homogeneously disordered NbN thin film.

  7. Gauss Sum Factorization with Cold Atoms

    SciTech Connect (OSTI)

    Gilowski, M.; Wendrich, T.; Mueller, T.; Ertmer, W.; Rasel, E. M. [Institut fuer Quantenoptik, Leibniz Universitaet Hannover, Welfengarten 1, D-30167 Hannover (Germany); Jentsch, Ch. [Astrium GmbH-Satellites, 88039 Friedrichshafen (Germany); Schleich, W. P. [Institut fuer Quantenphysik, Universitaet Ulm, Albert-Einstein-Allee 11, D-89081 Ulm (Germany)

    2008-01-25

    We report the first implementation of a Gauss sum factorization algorithm by an internal state Ramsey interferometer using cold atoms. A sequence of appropriately designed light pulses interacts with an ensemble of cold rubidium atoms. The final population in the involved atomic levels determines a Gauss sum. With this technique we factor the number N=263193.

  8. Atomic Representations of Rank 2 Graph Algebras

    E-Print Network [OSTI]

    Davidson, Ken

    Atomic Representations of Rank 2 Graph Algebras Kenneth R. Davidson a , Stephen C. Power b , Dilian University, Lancaster LA1 4YF, U.K. Abstract We provide a detailed analysis of atomic -representations- posed into a direct sum or direct integral of irreducible atomic representations. The building blocks

  9. PRODUCTION OF EXOTIC ATOMS MARK ELLERMANN II

    E-Print Network [OSTI]

    Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

    #12;PRODUCTION OF EXOTIC ATOMS by MARK ELLERMANN II Submitted to the Faculty of the Graduate School OF SCIENCE December 2010 #12;PRODUCTION OF EXOTIC ATOMS Approved: Adviser Dean of the College of Arts & Science Dean of Graduate Studies and Research ii #12;ABSTRACT PRODUCTION OF EXOTIC ATOMS Mark Ellermann

  10. The Future of Atomic Energy

    DOE R&D Accomplishments [OSTI]

    Fermi, E.

    1946-05-27

    There is definitely a technical possibility that atomic power may gradually develop into one of the principal sources of useful power. If this expectation will prove correct, great advantages can be expected to come from the fact that the weight of the fuel is almost negligible. This feature may be particularly valuable for making power available to regions of difficult access and far from deposits of coal. It also may prove a great asset in mobile power units for example in a power plant for ship propulsion. On the negative side there are some technical limitations to be applicability of atomic power of which perhaps the most serious is the impossibility of constructing light power units; also there will be some peculiar difficulties in operating atomic plants, as for example the necessity of handling highly radioactive substances which will necessitate, at least for some considerable period, the use of specially skilled personnel for the operation. But the chief obstacle in the way of developing atomic power will be the difficulty of organizing a large scale industrial development in an internationally safe way. This presents actually problems much more difficult to solve than any of the technical developments that are necessary, It will require an unusual amount of statesmanship to balance properly the necessity of allaying the international suspicion that arises from withholding technical secrets against the obvious danger of dumping the details of the procedures for an extremely dangerous new method of warfare on a world that may not yet be prepared to renounce war. Furthermore, the proper balance should be found in the relatively short time that will elapse before the 'secrets' will naturally become open knowledge by rediscovery on part of the scientists and engineers of other countries.

  11. Force Modulation System for Vehicle Manufacturing | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    System for Vehicle Manufacturing Force Modulation System for Vehicle Manufacturing Novel Technology Enables Energy-Efficient Production of High-Strength Steel Automotive Parts...

  12. David J. Gross and the Strong Force

    Office of Scientific and Technical Information (OSTI)

    described electromagnetism, the force that acts between charged particles, such as electrons and protons, and which governs all chemical interactions. That theory, called...

  13. Plasmonic lateral forces on chiral spheres

    E-Print Network [OSTI]

    Canaguier-Durand, Antoine

    2015-01-01

    We show that the optical force exerted on a finite size chiral sphere by a surface plasmon mode has a component along a direction perpendicular to the plasmon linear momentum. We reveal how this chiral lateral force, pointing in opposite directions for opposite enantiomers, stems from an angular-to-linear crossed momentum transfer involving the plasmon transverse spin angular momentum density and mediated by the chirality of the sphere. Our multipolar approach allows us discussing the inclusion of the recoil term in the force on a small sphere taken in the dipolar limit and observing sign inversions of the lateral chiral force when the size of the sphere increases.

  14. Interagency Energy Management Task Force Members

    Broader source: Energy.gov [DOE]

    The Interagency Energy Management Task Force is led by the Federal Energy Management Program director. Members include energy and sustainability managers from federal agencies.

  15. Reduction of the Casimir force using aerogels

    E-Print Network [OSTI]

    R. Esquivel-Sirvent

    2007-08-02

    By using silicon oxide based aerogels we show numerically that the Casimir force can be reduced several orders of magnitude, making its effect negligible in nanodevices. This decrease in the Casimir force is also present even when the aerogels are deposited on metallic substrates. To calculate the Casimir force we model the dielectric function of silicon oxide aerogels using an effective medium dielectric function such as the Clausius-Mossotti approximation. The results show that both the porosity of the aerogel and its thickness can be use as control parameters to reduce the magnitude of the Casimir force.

  16. Reduction of the Casimir force using aerogels

    E-Print Network [OSTI]

    Esquivel-Sirvent, R

    2007-01-01

    By using silicon oxide based aerogels we show numerically that the Casimir force can be reduced several orders of magnitude, making its effect negligible in nanodevices. This decrease in the Casimir force is also present even when the aerogels are deposited on metallic substrates. To calculate the Casimir force we model the dielectric function of silicon oxide aerogels using an effective medium dielectric function such as the Clausius-Mossotti approximation. The results show that both the porosity of the aerogel and its thickness can be use as control parameters to reduce the magnitude of the Casimir force.

  17. Thermodynamics and dynamics of atomic selforganization in an optical cavity

    E-Print Network [OSTI]

    Stefan Schütz; Simon B. Jäger; Giovanna Morigi

    2015-08-26

    Pattern formation of atoms in high-finesse optical resonators results from the mechanical forces of light associated with superradiant scattering into the cavity mode. It occurs when the laser intensity exceeds a threshold value, such that the pumping processes counteract the losses. We consider atoms driven by a laser and coupling with a mode of a standing-wave cavity and describe their dynamics with a Fokker-Planck equation, in which the atomic motion is semiclassical but the cavity field is a full quantum variable. The asymptotic state of the atoms is a thermal state, whose temperature is solely controlled by the detuning between the laser and the cavity frequency and by the cavity loss rate. From this result we derive the free energy and show that in the thermodynamic limit selforganization is a second-order phase transition. The order parameter is the field inside the resonator, to which one can associate a magnetization in analogy to ferromagnetism, the control field is the laser intensity, however the steady state is intrinsically out-of-equilibrium. In the symmetry-broken phase quantum noise induces jumps of the spatial density between two ordered patterns: We characterize the statistical properties of this temporal behaviour at steady state and show that the thermodynamic properties of the system can be extracted by detecting the light at the cavity output. The results of our analysis are in full agreement with previous studies, extend them by deriving a self-consistent theory which is valid also when the cavity field is in the shot-noise limit, and elucidate the nature of the selforganization transition.

  18. VOLUME 82, NUMBER 26 P H Y S I C A L R E V I E W L E T T E R S 28 JUNE 1999 Laser-Driven Atomic Pump

    E-Print Network [OSTI]

    Tománek, David

    by the direct force Fd due to the external field that is locally modified at the atomic site, and by the wind driving could be realized if the atoms would take better advantage of the large unidirectional momenta and energy carried by the hot electrons. This type of driving can be realized in photovoltaic materials

  19. Quantum Fuel with Multilevel Atomic Coherence for Ultrahigh Specific Work in a Photonic Carnot Engine

    E-Print Network [OSTI]

    Deniz Türkpençe; Özgür E. Müstecapl?o?lu

    2015-08-28

    We investigate scaling of work and efficiency of a photonic Carnot engine with the number of quantum coherent resources. Specifically, we consider a generalization of the "phaseonium fuel" for the photonic Carnot engine, which was first introduced as a three-level atom with two lower states in a quantum coherent superposition by [M. O. Scully, M. Suhail Zubairy, G. S. Agarwal, and H. Walther, Science 299, 862 (2003)], to the case of N+1 level atoms with N coherent lower levels. We take into account atomic relaxation and dephasing as well as the cavity loss and derive a coarse grained master equation to evaluate the work and efficiency, analytically. Analytical results are verified by microscopic numerical examination of the thermalization dynamics. We find that efficiency and work scale quadratically with the number of quantum coherent levels. Quantum coherence boost to the specific energy (work output per unit mass of the resource) is a profound fundamental difference of quantum fuel from classical resources. We consider typical modern resonator set ups and conclude that multilevel phaseonium fuel can be utilized to overcome the decoherence in available systems. Preparation of the atomic coherences and the associated cost of coherence are analyzed and the engine operation within the bounds of the second law is verified. Our results bring the photonic Carnot engines much closer to the capabilities of current resonator technologies.

  20. Quantum Fuel with Multilevel Atomic Coherence for Ultrahigh Specific Work in a Photonic Carnot Engine

    E-Print Network [OSTI]

    Deniz Türkpençe; Özgür E. Müstecapl?o?lu

    2015-10-08

    We investigate scaling of work and efficiency of a photonic Carnot engine with the number of quantum coherent resources. Specifically, we consider a generalization of the "phaseonium fuel" for the photonic Carnot engine, which was first introduced as a three-level atom with two lower states in a quantum coherent superposition by [M. O. Scully, M. Suhail Zubairy, G. S. Agarwal, and H. Walther, Science {\\bf 299}, 862 (2003)], to the case of $N+1$ level atoms with $N$ coherent lower levels. We take into account atomic relaxation and dephasing as well as the cavity loss and derive a coarse grained master equation to evaluate the work and efficiency, analytically. Analytical results are verified by microscopic numerical examination of the thermalization dynamics. We find that efficiency and work scale quadratically with the number of quantum coherent levels. Quantum coherence boost to the specific energy (work output per unit mass of the resource) is a profound fundamental difference of quantum fuel from classical resources. We consider typical modern resonator set ups and conclude that multilevel phaseonium fuel can be utilized to overcome the decoherence in available systems. Preparation of the atomic coherences and the associated cost of coherence are analyzed and the engine operation within the bounds of the second law is verified. Our results bring the photonic Carnot engines much closer to the capabilities of current resonator technologies.