National Library of Energy BETA

Sample records for atomic force microscopy

  1. 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 ...

  2. 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

  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. 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

  5. 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.

  6. 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...

  7. 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.

  8. 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

  9. 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.

  10. 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 ...

  11. 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.

  12. 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

  13. 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

  14. 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.

  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. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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 ...

  5. 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...

  6. 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.

  7. 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...

  8. 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.

  9. 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...

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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”).

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Spatially resolved low-frequency noise measured by atomic force microscopy Lynda Cockins, Yoichi Miyahara,* and Peter Grutter

    E-Print Network [OSTI]

    Grütter, Peter

    about the location of each trap even if a single trap is involved. Scanning tunneling microscopy has to traps located near noninsulating surfaces because a tunneling current of at least several picoamperes with surface InAs quantum dots and a buried two-dimensional electron gas. The observed noise exhibits

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  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. Physical mechanisms of megahertz vibrations and nonlinear detection in ultrasonic force and related microscopies

    SciTech Connect (OSTI)

    Bosse, J. L.; Huey, B. D. [Department of Materials Science and Engineering, 97 North Eagleville Road, Unit 3136, Storrs, Connecticut 06269-3136 (United States); Tovee, P. D.; Kolosov, O. V., E-mail: o.kolosov@lancaster.ac.uk [Department of Physics, Lancaster University, Lancaster LA1 4YB (United Kingdom)

    2014-04-14

    Use of high frequency (HF) vibrations at MHz frequencies in Atomic Force Microscopy (AFM) advanced nanoscale property mapping to video rates, allowed use of cantilever dynamics for mapping nanomechanical properties of stiff materials, sensing ?s time scale phenomena in nanostructures, and enabled detection of subsurface features with nanoscale resolution. All of these methods critically depend on the generally poor characterized HF behaviour of AFM cantilevers in contact with a studied sample, spatial and frequency response of piezotransducers, and transfer of ultrasonic vibrations between the probe and a specimen. Focusing particularly on Ultrasonic Force Microscopy (UFM), this work is also applicable to waveguide UFM, heterodyne force microscopy, and near-field holographic microscopy, all methods that exploit nonlinear tip-surface force interactions at high frequencies. Leveraging automated multidimensional measurements, spectroscopic UFM (sUFM) is introduced to investigate a range of common experimental parameters, including piezotransducer excitation frequency, probed position, ultrasonic amplitude, cantilever geometry, spring constant, and normal force. Consistent with studies of influence of each of these factors, the data-rich sUFM signatures allow efficient optimization of ultrasonic-AFM based measurements, leading to best practices recommendations of using longer cantilevers with lower fundamental resonance, while at the same time increasing the central frequency of HF piezo-actuators, and only comparing results within areas on the order of few ?m{sup 2} unless calibrated directly or compared with in-the-imaged area standards. Diverse materials such as Si, Cr, and photoresist are specifically investigated. This work thereby provides essential insight into the reliable use of MHz vibrations with AFM and provides direct evidence substantiating phenomena such as sensitivity to adhesion, diminished friction for certain ultrasonic conditions, and the particular benefit of UFM and related methods for nanoscale mapping of stiff materials.

  20. 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 ...

  1. 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.

  2. Spark-gap atomic emission microscopy. II. Improvements in resolution P. G. Van Patten,a)

    E-Print Network [OSTI]

    Myrick, Michael Lenn

    Spark-gap atomic emission microscopy. II. Improvements in resolution P. G. Van Patten,a) J. D. Noll which enhance performance in spark-gap atomic emission microscopy SGAEM experiments. SGAEM is a recent as small as 5 V, and intense atomic emission has been observed in such sparks. Small 1 nF , high

  3. 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 ...

  4. 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 ...

  5. Static Stern-Gerlach effect in magnetic force microscopy G. P. Berman,1

    E-Print Network [OSTI]

    Hammel, P. Chris

    Static Stern-Gerlach effect in magnetic force microscopy G. P. Berman,1 G. D. Doolen,1 P. C. Hammel February 2002 We examine static single-spin measurements using magnetic-force microscopy methods. We show, 07.79.Pk I. INTRODUCTION The Stern-Gerlach SG effect, one of the cornerstones of a quantum mechanics

  6. Cross-sectional electrostatic force microscopy of thin-film solar cells

    SciTech Connect (OSTI)

    Ballif, C.; Moutinho, H. R.; Al-Jassim, M. M.

    2001-01-15

    In a recent work, we showed that atomic force microscopy (AFM) is a powerful technique to image cross sections of polycrystalline thin films. In this work, we apply a modification of AFM, namely, electrostatic force microscopy (EFM), to investigate the electronic properties of cleaved II--VI and multijunction thin-film solar cells. We cleave the devices in such a way that they are still working with their nominal photovoltaic efficiencies and can be polarized for the measurements. This allows us to differentiate between surface effects (work function and surface band bending) and bulk device properties. In the case of polycrystalline CdTe/CdS/SnO{sub 2}/glass solar cells, we find a drop of the EFM signal in the area of the CdTe/CdS interface ({+-}50 nm). This drop varies in amplitude and sign according to the applied external bias and is compatible with an n-CdS/p-CdTe heterojunction model, thereby invalidating the possibility of a deeply buried n-p CdTe homojunction. In the case of a triple-junction GaInP/GaAs/Ge device, we observe a variation of the EFM signal linked to both the material work-function differences and to the voltage bias applied to the cell. We attempt a qualitative explanation of the results and discuss the implications and difficulties of the EFM technique for the study of such thin-film devices.

  7. ORNL microscopy pencils patterns in polymers at the nanoscale...

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

    (865) 574-7308 ORNL microscopy pencils patterns in polymers at the nanoscale Oak Ridge National Laboratory researchers used atomic force microscopy to draw nanoscale patterns in a...

  8. Electrochemical Monitoring of TiO2 Atomic Layer Deposition by Chronoamperometry and Scanning Electrochemical Microscopy

    E-Print Network [OSTI]

    Yu, Edward T.

    Electrochemical Monitoring of TiO2 Atomic Layer Deposition by Chronoamperometry and Scanning) was used to characterize the atomic layer deposition (ALD) of TiO2 on indium-doped tin oxide (ITO). KEYWORDS: atomic layer deposition (ALD), scanning electrochemical microscopy (SECM), nanoporous films

  9. 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

  10. 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...

  11. 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...

  12. 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

  13. 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

  14. 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.

  15. 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.

  16. Scanning probe microscopy imaging before and after atomic layer oxide deposition on a compound semiconductor surface

    E-Print Network [OSTI]

    Kummel, Andrew C.

    Scanning probe microscopy imaging before and after atomic layer oxide deposition on a compound fabricated using trimethylaluminum (TMA) and water atomic layer deposition (ALD) for the Al2O3 gate oxide level (Fig 2) suggesting that an ordered monolayer layer might be a requirement for unpinning

  17. Atom probe field ion microscopy and related topics: A bibliography 1990

    SciTech Connect (OSTI)

    Russell, K.F.; Miller, M.K.

    1991-12-01

    This bibliography includes references related to the following topics: atom probe field ion microscopy (APFIM), field ion microscopy (FIM), field emission (FE), ion sources, and field desorption mass microscopy (FDMM). Technique-orientated studies and applications are included. The bibliography covers the period 1990. The references contained in this document were compiled from a variety of sources including computer searches and personal lists of publications. To reduce the length of this document, the references have been reduced to the minimum necessary to locate the articles. The references, listed alphabetically by authors, are subdivided into the categories listed in paragraph one above. An Addendum of references missed in previous bibliographies is included.

  18. Characteristics of cooperative spontaneous radiation with applications to atom microscopy and coherent XUV radiation generation 

    E-Print Network [OSTI]

    Chang, Juntao

    2009-05-15

    * . . . . . . . . . . . . . . . . . . . . . . . . . . 48 A. Far-feld Optical Microscopy and Diffraction Limit . . . . . 49 B. Atom Localization via Resonant Fluorescence . . . . . . . 50 C. Master Equation of the System . . . . . . . . . . . . . . . 53 D. Resonant Fluorescence Spectrum and Distance... the cooperative emission from a system of uncorrelated excited atoms. This process is usually started by normal spontaneous emission but later results in correlation within the system. Feld et al. then developed a semiclassical theory for superradiance...

  19. Traction force microscopy on soft elastic substrates: a guide to recent computational advances

    E-Print Network [OSTI]

    Ulrich S. Schwarz; Jerome R. D. Soine

    2015-06-08

    The measurement of cellular traction forces on soft elastic substrates has become a standard tool for many labs working on mechanobiology. Here we review the basic principles and different variants of this approach. In general, the extraction of the substrate displacement field from image data and the reconstruction procedure for the forces are closely linked to each other and limited by the presence of experimental noise. We discuss different strategies to reconstruct cellular forces as they follow from the foundations of elasticity theory, including two- versus three-dimensional, inverse versus direct and linear versus non-linear approaches. We also discuss how biophysical models can improve force reconstruction and comment on practical issues like substrate preparation, image processing and the availability of software for traction force microscopy.

  20. 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.

  1. 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...

  2. 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.

  3. 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.

  4. 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

  5. Three-Dimensional Quantification of Cellular Traction Forces and Mechanosensing of Thin Substrata by Fourier Traction Force Microscopy

    E-Print Network [OSTI]

    Juan C del Alamo; Ruedi Meili; Begoña Alvarez-Gonzalez; Baldomero Alonso-Latorre; Effie Bastounis; Richard Firtel; Juan C Lasheras

    2013-06-18

    We introduce a novel three-dimensional (3D) traction force microscopy (TFM) method motivated by the recent discovery that cells adhering on plane surfaces exert both in-plane and out-of-plane traction stresses. We measure the 3D deformation of the substratum on a thin layer near its surface, and input this information into an exact analytical solution of the elastic equilibrium equation. These operations are performed in the Fourier domain with high computational efficiency, allowing to obtain the 3D traction stresses from raw microscopy images virtually in real time. We also characterize the error of previous two-dimensional (2D) TFM methods that neglect the out-of-plane component of the traction stresses. This analysis reveals that, under certain combinations of experimental parameters (\\ie cell size, substratums' thickness and Poisson's ratio), the accuracy of 2D TFM methods is minimally affected by neglecting the out-of-plane component of the traction stresses. Finally, we consider the cell's mechanosensing of substratum thickness by 3D traction stresses, finding that, when cells adhere on thin substrata, their out-of-plane traction stresses can reach four times deeper into the substratum than their in-plane traction stresses. It is also found that the substratum stiffness sensed by applying out-of-plane traction stresses may be up to 10 times larger than the stiffness sensed by applying in-plane traction stresses.

  6. Magnetic force microscopy method and apparatus to detect and image currents in integrated circuits

    DOE Patents [OSTI]

    Campbell, A.N.; Anderson, R.E.; Cole, E.I. Jr.

    1995-11-07

    A magnetic force microscopy method and improved magnetic tip for detecting and quantifying internal magnetic fields resulting from current of integrated circuits are disclosed. Detection of the current is used for failure analysis, design verification, and model validation. The interaction of the current on the integrated chip with a magnetic field can be detected using a cantilevered magnetic tip. Enhanced sensitivity for both ac and dc current and voltage detection is achieved with voltage by an ac coupling or a heterodyne technique. The techniques can be used to extract information from analog circuits. 17 figs.

  7. Magnetic force microscopy method and apparatus to detect and image currents in integrated circuits

    DOE Patents [OSTI]

    Campbell, Ann. N. (13170-B Central SE #188, Albuquerque, NM 87123); Anderson, Richard E. (2800 Tennessee NE, Albuquerque, NM 87110); Cole, Jr., Edward I. (2116 White Cloud NE, Albuquerque, NM 87112)

    1995-01-01

    A magnetic force microscopy method and improved magnetic tip for detecting and quantifying internal magnetic fields resulting from current of integrated circuits. Detection of the current is used for failure analysis, design verification, and model validation. The interaction of the current on the integrated chip with a magnetic field can be detected using a cantilevered magnetic tip. Enhanced sensitivity for both ac and dc current and voltage detection is achieved with voltage by an ac coupling or a heterodyne technique. The techniques can be used to extract information from analog circuits.

  8. Out of equilibrium GigaPa Young modulus of water nanobridge probed by Force Feedback Microscopy

    E-Print Network [OSTI]

    Carpentier, Simon; Costa, Luca; Vitorino, Miguel V; Charlaix, Elisabeth; Chevrier, Joel

    2015-01-01

    Because of capillary condensation, water droplets appear in nano/micropores. The large associated surface interactions can deeply influence macroscopic properties as in granular media. We report that dynamical properties of such nanobridge dramatically change when probed at different time scales. Using a novel AFM mode, the Force Feedback Microscopy, the gap between the nanotip and the surface is continuously varied, and we observe this change in the simultaneous measurements, at different frequencies, of the stiffness G'(N/m), the dissipative coefficient G"(kg/sec) together with the static force. As the measuring time approaches the microsecond, the liquid droplet exhibits a large positive stiffness (it is small and negative in the long time limit). Although clearly controlled by surface effects, it compares to the stiffness of a solid nanobridge with a 1 GigaPa Young modulus. We argue that as evaporation and condensation gradually lose efficiency, the contact line progressively becomes immobile, which expla...

  9. 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.

  10. 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.

  11. Spark-Gap Atomic Emission Microscopy P. G. Van Patten, J. D. Noll, and M. L. Myrick*

    E-Print Network [OSTI]

    Myrick, Michael Lenn

    Spark-Gap Atomic Emission Microscopy P. G. Van Patten, J. D. Noll, and M. L. Myrick* Department been developed. The technique is based on spark atomic emission spectroscopy and provides information the sample and cause emission. Spectra from a polished copper electrode surface are presented and discussed

  12. Atomic-scale electrochemistry on the surface of a manganite by scanning tunneling microscopy

    SciTech Connect (OSTI)

    Vasudevan, Rama K. Tselev, Alexander; Baddorf, Arthur P.; Gianfrancesco, Anthony G.

    2015-04-06

    The doped manganese oxides (manganites) have been widely studied for their colossal magnetoresistive effects, for potential applications in oxide spintronics, electroforming in resistive switching devices, and are materials of choice as cathodes in modern solid oxide fuel cells. However, little experimental knowledge of the dynamics of the surfaces of perovskite manganites at the atomic scale exists. Here, through in-situ scanning tunneling microscopy (STM), we demonstrate atomic resolution on samples of La{sub 0.625}Ca{sub 0.375}MnO{sub 3} grown on (001) SrTiO{sub 3} by pulsed laser deposition. Furthermore, by applying triangular DC waveforms of increasing amplitude to the STM tip, and measuring the tunneling current, we demonstrate the ability to both perform and monitor surface electrochemical processes at the atomic level, including formation of oxygen vacancies and removal and deposition of individual atomic units or clusters. Our work paves the way for better understanding of surface oxygen reactions in these systems.

  13. 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. ...

  14. 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 ...

  15. Direct determination of the local Hamaker constant of inorganic surfaces based on scanning force microscopy

    SciTech Connect (OSTI)

    Krajina, Brad A.; Kocherlakota, Lakshmi S.; Overney, René M., E-mail: roverney@u.washington.edu [Department of Chemical Engineering, University of Washington, Seattle, Washington 98195-1750 (United States)

    2014-10-28

    The energetics involved in the bonding fluctuations between nanometer-sized silicon dioxide (SiO{sub 2}) probes and highly oriented pyrolytic graphite (HOPG) and molybdenum disulfide (MoS{sub 2}) could be quantified directly and locally on the submicron scale via a time-temperature superposition analysis of the lateral forces between scanning force microscopy silicon dioxide probes and inorganic sample surfaces. The so-called “intrinsic friction analysis” (IFA) provided direct access to the Hamaker constants for HOPG and MoS{sub 2}, as well as the control sample, calcium fluoride (CaF{sub 2}). The use of scanning probe enables nanoscopic analysis of bonding fluctuations, thereby overcoming challenges associated with larger scale inhomogeneity and surface roughness common to conventional techniques used to determine surface free energies and dielectric properties. A complementary numerical analysis based on optical and electron energy loss spectroscopy and the Lifshitz quantum electrodynamic theory of van der Waals interactions is provided and confirms quantitatively the IFA results.

  16. 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

  17. 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

  18. Piezoelectricity and ferroelectricity of cellular polypropylene electrets films characterized by piezoresponse force microscopy

    SciTech Connect (OSTI)

    Miao, Hongchen; Sun, Yao; Zhou, Xilong; Li, Yingwei; Li, Faxin

    2014-08-14

    Cellular electrets polymer is a new ferroelectret material exhibiting large piezoelectricity and has attracted considerable attentions in researches and industries. Property characterization is very important for this material and current investigations are mostly on macroscopic properties. In this work, we conduct nanoscale piezoelectric and ferroelectric characterizations of cellular polypropylene (PP) films using piezoresponse force microscopy (PFM). First, both the single-frequency PFM and dual-frequency resonance-tracking PFM testings were conducted on the cellular PP film. The localized piezoelectric constant d{sub 33} is estimated to be 7–11pC/N by correcting the resonance magnification with quality factor and it is about one order lower than the macroscopic value. Next, using the switching spectroscopy PFM (SS-PFM), we studied polarization switching behavior of the cellular PP films. Results show that it exhibits the typical ferroelectric-like phase hysteresis loops and butterfly-shaped amplitude loops, which is similar to that of a poly(vinylidene fluoride) (PVDF) ferroelectric polymer film. However, both the phase and amplitude loops of the PP film are intensively asymmetric, which is thought to be caused by the nonzero remnant polarization after poling. Then, the D-E hysteresis loops of both the cellular PP film and PVDF film were measured by using the same wave form as that used in the SS-PFM, and the results show significant differences. Finally, we suggest that the ferroelectric-like behavior of cellular electrets films should be distinguished from that of typical ferroelectrics, both macroscopically and microscopically.

  19. 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.

  20. 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

  1. Mechanical Property Measurements of Membranes and Viruses by Using Fluorescence Interference Contrast Microscopy and Atomic Force Microscopy

    E-Print Network [OSTI]

    Gui, Dong

    2013-01-01

    by Quasi-elastic Neutron Scattering. Biochemistry 41:13078-by Quasi-elastic Neutron Scattering. Biochemistry 41:13078-A small- angle neutron scattering study. Biochim. Biophys.

  2. 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.

  3. 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.

  4. 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...

  5. 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...

  6. 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

  7. 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

  8. 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

  9. 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.

  10. 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...

  11. 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

  12. 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

  13. 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

  14. 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...

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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.

  20. Atom microscopy via two-photon spontaneous emission spectroscopy RID A-5077-2009 

    E-Print Network [OSTI]

    Qamar, Sajid; Evers, Joerg; Zubairy, M. Suhail

    2009-01-01

    We study subwavelength position measurement via spontaneous emission spectroscopy with two photons. Our model systems are a single Lambda-type three-level atom, in which a dual interaction generates two independent photons, and an M-type five...

  1. 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

  2. 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.

  3. 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.

  4. Micro- and nanodomain imaging in uniaxial ferroelectrics: Joint application of optical, confocal Raman, and piezoelectric force microscopy

    SciTech Connect (OSTI)

    Shur, V. Ya., E-mail: vladimir.shur@urfu.ru; Zelenovskiy, P. S. [Ferroelectric Laboratory, Institute of Natural Sciences, Ural Federal University, 620000 Ekaterinburg (Russian Federation)

    2014-08-14

    The application of the most effective methods of the domain visualization in model uniaxial ferroelectrics of lithium niobate (LN) and lithium tantalate (LT) family, and relaxor strontium-barium niobate (SBN) have been reviewed in this paper. We have demonstrated the synergetic effect of joint usage of optical, confocal Raman, and piezoelectric force microscopies which provide extracting of the unique information about formation of the micro- and nanodomain structures. The methods have been applied for investigation of various types of domain structures with increasing complexity: (1) periodical domain structure in LN and LT, (2) nanodomain structures in LN, LT, and SBN, (3) nanodomain structures in LN with modified surface layer, (4) dendrite domain structure in LN. The self-assembled appearance of quasi-regular nanodomain structures in highly non-equilibrium switching conditions has been considered.

  5. 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.

  6. Open-core screw dislocations in GaN epilayers observed by scanning force microscopy and high-resolution transmission electron microscopy

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    -resolution transmission electron microscopy W. Qian, G. S. Rohrer, and M. Skowronski Department of Materials Science. K. Gaskill Laboratory for Advanced Material Synthesis, Naval Research Laboratory, Washington, DC of organometallic vapor phase epitaxy grown -GaN films using high-resolution transmission electron microscopy

  7. Optimal experimental design for the detection of light atoms from high-resolution scanning transmission electron microscopy images

    SciTech Connect (OSTI)

    Gonnissen, J.; De Backer, A.; Martinez, G. T.; Van Aert, S.; Dekker, A. J. den; Rosenauer, A.; Sijbers, J.

    2014-08-11

    We report an innovative method to explore the optimal experimental settings to detect light atoms from scanning transmission electron microscopy (STEM) images. Since light elements play a key role in many technologically important materials, such as lithium-battery devices or hydrogen storage applications, much effort has been made to optimize the STEM technique in order to detect light elements. Therefore, classical performance criteria, such as contrast or signal-to-noise ratio, are often discussed hereby aiming at improvements of the direct visual interpretability. However, when images are interpreted quantitatively, one needs an alternative criterion, which we derive based on statistical detection theory. Using realistic simulations of technologically important materials, we demonstrate the benefits of the proposed method and compare the results with existing approaches.

  8. Understanding Atom Probe Tomography of Oxide-Supported Metal Nanoparticles by Correlation with Atomic Resolution Electron Microscopy and Field Evaporation Simulation

    SciTech Connect (OSTI)

    Devaraj, Arun; Colby, Robert J.; Vurpillot, F.; Thevuthasan, Suntharampillai

    2014-03-26

    Metal-dielectric composite materials, specifically metal nanoparticles supported on or embedded in metal oxides, are widely used in catalysis. The accurate optimization of such nanostructures warrants the need for detailed three-dimensional characterization. Atom probe tomography is uniquely capable of generating sub-nanometer structural and compositional data with part-per-million mass sensitivity, but there are reconstruction artifacts for composites containing materials with strongly differing fields of evaporation, as for oxide-supported metal nanoparticles. By correlating atom probe tomography with scanning transmission electron microscopy for Au nanoparticles embedded in an MgO support, deviations from an ideal topography during evaporation are demonstrated directly, and correlated with compositional errors in the reconstructed data. Finite element simulations of the field evaporation process confirm that protruding Au nanoparticles will evolve on the tip surface, and that evaporation field variations lead to an inaccurate assessment of the local composition, effectively lowering the spatial resolution of the final reconstructed dataset. Cross-correlating the experimental data with simulations results in a more detailed understanding of local evaporation aberrations during APT analysis of metal-oxide composites, paving the way towards a more accurate three-dimensional characterization of this technologically important class of materials.

  9. Directly correlated transmission electron microscopy and atom probe tomography of grain boundary oxidation in a Ni-Al binary alloy exposed to high-temperature water.

    SciTech Connect (OSTI)

    Schreiber, Daniel K.; Olszta, Matthew J.; Bruemmer, Stephen M.

    2013-10-30

    Intergranular oxidation of a Ni-4Al alloy exposed to hydrogenated, high-temperature water was characterized using directly correlated transmission electron microscopy and atom probe tomography. These combined analyses revealed that discrete, well-separated oxides (NiAl2O4) precipitated along grain boundaries in the metal. Aluminum was depleted from the grain boundary between oxides and also from one side of the boundary as a result of grain boundary migration. The discrete oxide morphology, disconnected from the continuous surface oxidation, suggests intergranular solid-state internal oxidation of Al. Keywords: oxidation; grain boundaries; nickel alloys; atom probe tomography; transmission electron microscopy (TEM)

  10. Ultrafast pump-probe force microscopy with nanoscale resolution Junghoon Jahng, Jordan Brocious, Dmitry A. Fishman, Steven Yampolsky, Derek Nowak, Fei Huang, Vartkess

    E-Print Network [OSTI]

    Potma, Eric Olaf

    Ultrafast pump-probe force microscopy with nanoscale resolution Junghoon Jahng, Jordan Brocious and reconfigurable setup for all-terahertz time-resolved pump-probe spectroscopy Rev. Sci. Instrum. 83, 053107 (2012); 10.1063/1.4717732 Femtosecond time-resolved optical pump-probe spectroscopy at kilohertz

  11. 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.

  12. 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...

  13. Optical, ferroelectric, and piezoresponse force microscopy studies of pulsed laser deposited Aurivillius Bi?FeTi?O?? thin films

    SciTech Connect (OSTI)

    Kooriyattil, Sudheendran [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, P.O. Box 70377, San Juan, Puerto Rico 00936-8377 (United States); Department of Physics, Sree Kerala Varma College, Thrissur-680011, Kerala (India); Pavunny, Shojan P., E-mail: rkatiyar@uprrp.edu, E-mail: shojanpp@gmail.com; Barrionuevo, Danilo; Katiyar, Ram S., E-mail: rkatiyar@uprrp.edu, E-mail: shojanpp@gmail.com [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, P.O. Box 70377, San Juan, Puerto Rico 00936-8377 (United States)

    2014-10-14

    Bi?FeTi?O?? (BFTO) based Aurivillius ferroelectric thin films were fabricated on strontium ruthanate coated amorphous fused silica substrates using pulsed laser deposition technique. Optical, ferroelectric, and piezoresponse properties of these thin films were investigated. The estimated refractive index (n) and extinction coefficient (k) for these films were in the range from 2.40 to 2.59 and 0.012 to 0.19, respectively. The bandgap of the BFTO thin layers was estimated to be 2.88 eV. Domain switching and hysteresis loops of BFTO films were studied utilizing piezoresponse force microscopy (PFM). The measured apparent polarization (P{sub r}) and coercive field (E{sub c}) for the samples were 20 ?C/cm² and 250 kV/cm, respectively. The amplitude and phase hysteresis curves obtained from PFM characterization reveal that these films can be switched below 5 V. These results suggest that BFTO in thin film form is a promising material for photo ferroelectric and optoelectronic devices applications.

  14. Hybrid near-field scanning optical microscopy tips for live cell measurements

    E-Print Network [OSTI]

    Kapkiai, Luka K.; Moore-Nichols, David; Carnell, Jonathan; Krogmeier, Jeffrey R.; Dunn, Robert C.

    2004-03-08

    atomic force microscopy cantilever. Imaging of fluorescent latex spheres suspended in an acetate matrix demonstrates the subdiffraction limited fluorescence and topography capabilities of the tips. The reduced spring constant of the hybrid tip is also...

  15. 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

  16. Atomic-resolution study of polarity reversal in GaSb grown on Si by scanning transmission electron microscopy

    SciTech Connect (OSTI)

    Hosseini Vajargah, S.; Woo, S. Y.; Botton, G. A.; Ghanad-Tavakoli, S.; Kleiman, R. N.; Preston, J. S.

    2012-11-01

    The atomic-resolved reversal of the polarity across an antiphase boundary (APB) was observed in GaSb films grown on Si by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The investigation of the interface structure at the origin of the APB reveals that coalescence of two domains with Ga-prelayer and Sb-prelayer causes the sublattice reversal. The local strain and lattice rotation distributions of the APB, attributed to the discordant bonding length at the APB with the surrounding GaSb lattice, were further studied using the geometric phase analysis technique. The crystallographic characteristics of the APBs and their interaction with other planar defects were observed with HAADF-STEM. The quantitative agreement between experimental and simulated images confirms the observed polarities in the acquired HAADF-STEM data. The self-annihilation mechanism of the APBs is addressed based on the rotation induced by anti-site bonds and APBs' faceting.

  17. 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.

  18. 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.

  19. 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.

  20. Electron Microscopy Observation of TiO2 Nanocrystal Evolution in High-Temperature Atomic Layer Deposition

    E-Print Network [OSTI]

    Wang, Xudong

    ABSTRACT: Understanding the evolution of amorphous and crystalline phases during atomic layer deposition nanorods via the principle of vapor-phase oriented attachment. KEYWORDS: TiO2, atomic layer deposition, Ostwald-Lussac law, oriented attachment Atomic layer deposition (ALD) is a unique thin film growth

  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. 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...

  4. 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.

  5. 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.

  6. Probing Nanostructures for Photovoltaics: Using atomic force microscopy and other tools to characterize nanoscale materials for harvesting solar energy

    E-Print Network [OSTI]

    Zaniewski, Anna Monro

    2012-01-01

    literature . . . . . . 3.1.2 Photovoltaic cells based on CuConjugated polymer photovoltaic cells. Chem. Mater. , 16:for e?cient photovoltaic cells. Nature Nanotechnology, 6:

  7. Probing Nanostructures for Photovoltaics: Using atomic force microscopy and other tools to characterize nanoscale materials for harvesting solar energy

    E-Print Network [OSTI]

    Zaniewski, Anna Monro

    2012-01-01

    and Outlook Transparent top contact Rear contact Figure 3.10: Schematic of a solarsolar cells is a di?cult combination to fabricate. Summary and Future Outlooksolar cell surface to enable better light absorption. ?T = Summary and Future Outlook

  8. Novel approaches to investigate behaviors of bacteria by atomic force microscopy and circulating tumor cells through microfluidics

    E-Print Network [OSTI]

    Gray, David Steven

    2014-01-01

    The adaptability and apparent ingenuity of renegade and intruding cells within the human body present formidable challenges in warding off disease. As the longevity of humans increases, cancer will afflict greater numbers, ...

  9. Probing Nanostructures for Photovoltaics: Using atomic force microscopy and other tools to characterize nanoscale materials for harvesting solar energy

    E-Print Network [OSTI]

    Zaniewski, Anna Monro

    2012-01-01

    v List of Tables vii 1 Introduction 1.1 Photovoltaicsand J. V. Manca. Prog. Photovoltaics Res. Appl. , 15:713,polymer blends. Prog. Photovoltaics Res. Appl. , 15:727,

  10. A new technique for imaging Mineralized Fibrils on Bovine Trabecular Bone Fracture Surfaces by Atomic Force Microscopy

    E-Print Network [OSTI]

    Hansma, Paul

    A new technique for imaging Mineralized Fibrils on Bovine Trabecular Bone Fracture Surfaces coated with extrafibrillar mineral particles. The mineral particles are distinctly different in different collagen fibrils. If the observed particles can be verified to be native extrafibrillar mineral, this could

  11. Probing Nanostructures for Photovoltaics: Using atomic force microscopy and other tools to characterize nanoscale materials for harvesting solar energy

    E-Print Network [OSTI]

    Zaniewski, Anna Monro

    2012-01-01

    4.2.1 Organic solar cellOrganic Solar Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.3.1 Organic solar cell materials . . . . .

  12. Probing Nanostructures for Photovoltaics: Using atomic force microscopy and other tools to characterize nanoscale materials for harvesting solar energy

    E-Print Network [OSTI]

    Zaniewski, Anna Monro

    2012-01-01

    solar cell e?ciency is calculated as: W ork E sun Given the total energy input of the sun, and equationEnergy balance equations were used to model the e?ciency of the solar

  13. Probing Nanostructures for Photovoltaics: Using atomic force microscopy and other tools to characterize nanoscale materials for harvesting solar energy

    E-Print Network [OSTI]

    Zaniewski, Anna Monro

    2012-01-01

    the many-layer-graphene/semiconductor interface by doping.opened, turning graphene into a semiconductor which could begraphene is sometimes referred to as a ’zero gap’ semiconductor. [

  14. Probing Nanostructures for Photovoltaics: Using atomic force microscopy and other tools to characterize nanoscale materials for harvesting solar energy

    E-Print Network [OSTI]

    Zaniewski, Anna Monro

    2012-01-01

    for conventionally produced multijunction cells, as variousfor nanorod based multijunction cells. Chapter 4 A one-stepGaInP/GaInAs/Ge multijunction solar cells. Applied Physics

  15. Scanning tunneling microscopy/spectroscopy study of atomic and electronic structures of In2O on InAs and In0.53Ga0.47As,,001...-,,42... surfaces

    E-Print Network [OSTI]

    Kummel, Andrew C.

    Scanning tunneling microscopy/spectroscopy study of atomic and electronic structures of In2O on In trap density.4 On an atomic level, electronic defects result from strong perturbations to the electronic structure of the oxide/ semiconductor interface forming interface trap states. These perturbations

  16. 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.

  17. 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.

  18. 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.

  19. The structures and dynamics of atomic and molecular adsorbates on metal surfaces by scanning tunneling microscopy and low energy electron diffraction

    SciTech Connect (OSTI)

    Yoon, Hyungsuk Alexander

    1996-12-01

    Studies of surface structure and dynamics of atoms and molecules on metal surfaces are presented. My research has focused on understanding the nature of adsorbate-adsorbate and adsorbate-substrate interactions through surface studies of coverage dependency and coadsorption using both scanning tunneling microscopy (STM) and low energy electron diffraction (LEED). The effect of adsorbate coverage on the surface structures of sulfur on Pt(111) and Rh(111) was examined. On Pt(111), sulfur forms p(2x2) at 0.25 ML of sulfur, which transforms into a more compressed ({radical}3x{radical}3)R30{degrees} at 0.33 ML. On both structures, it was found that sulfur adsorbs only in fcc sites. When the coverage of sulfur exceeds 0.33 ML, it formed more complex c({radical}3x7)rect structure with 3 sulfur atoms per unit cell. In this structure, two different adsorption sites for sulfur atoms were observed - two on fcc sites and one on hcp site within the unit cell.

  20. 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.

  1. Probing graphene defects and estimating graphene quality with optical microscopy

    SciTech Connect (OSTI)

    Lai, Shen [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Center for Human Interface Nanotechnology (HINT), Suwon 440-746 (Korea, Republic of); Kyu Jang, Sung [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Jae Song, Young, E-mail: yjsong@skku.edu [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Department of Physics, Sungkyunkwan University (SKKU), Suwon 440-746 (Korea, Republic of); Lee, Sungjoo, E-mail: leesj@skku.edu [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Center for Human Interface Nanotechnology (HINT), Suwon 440-746 (Korea, Republic of); College of Information and Communication Engineering, Sungkyunkwan University (SKKU), Suwon 440-746 (Korea, Republic of)

    2014-01-27

    We report a simple and accurate method for detecting graphene defects that utilizes the mild, dry annealing of graphene/Cu films in air. In contrast to previously reported techniques, our simple approach with optical microscopy can determine the density and degree of dislocation of defects in a graphene film without inducing water-related damage or functionalization. Scanning electron microscopy, confocal Raman and atomic force microscopy, and X-ray photoelectron spectroscopy analysis were performed to demonstrate that our nondestructive approach to characterizing graphene defects with optimized thermal annealing provides rapid and comprehensive determinations of graphene quality.

  2. 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.

  3. Imaging individual lanthanum atoms in zeolite Y by scanning transmission electron microscopy: evidence of lanthanum pair sites

    SciTech Connect (OSTI)

    Xu, Pinghong; Lu, Jing; Aydin, C.; Debefve, Louise M.; Browning, Nigel D.; Chen, Cong-Yan; Gates, Bruce C.

    2015-09-01

    Images of La-exchanged NaY zeolite obtained with aberration-corrected scanning transmission electron microscopy (STEM) show that about 80% of the La cations were present as site-isolated species, with the remainder in pair sites. The distance between La cations in the pair sites ranged from 1.44 to 3.84 Å, consistent with the presence of pairs of cations tilted at various angles with respect to the support surface. The actual distance between La cations in the pair sites is inferred to be approximately 3.84 Å, which is shorter than the distance between the nearest Al sites in the zeolite (4.31 Å). The results therefore suggest the presence of dimeric structures of La cations bridged with OH groups, and the presence of such species has been inferred previously on the basis of X-ray photoelectron spectroscopy (W. Grünert, U. Sauerlandt, R. Schlögl, H.G. Karge, J. Phys. Chem., 97 (1993) 1413).

  4. 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

  5. [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.

  6. Evaluation of the electrical contact area in contact-mode scanning probe microscopy

    SciTech Connect (OSTI)

    Celano, Umberto E-mail: u.celano@gmail.com; Chintala, Ravi Chandra; Vandervorst, Wilfried; Hantschel, Thomas; Giammaria, Guido; Conard, Thierry; Bender, Hugo

    2015-06-07

    The tunneling current through an atomic force microscopy (AFM) tip is used to evaluate the effective electrical contact area, which exists between tip and sample in contact-AFM electrical measurements. A simple procedure for the evaluation of the effective electrical contact area is described using conductive atomic force microscopy (C-AFM) in combination with a thin dielectric. We characterize the electrical contact area for coated metal and doped-diamond tips operated at low force (<200 nN) in contact mode. In both cases, we observe that only a small fraction (<10?nm{sup 2}) of the physical contact (?100?nm{sup 2}) is effectively contributing to the transport phenomena. Assuming this reduced area is confined to the central area of the physical contact, these results explain the sub-10?nm electrical resolution observed in C-AFM measurements.

  7. Subwavelength optical microscopy in the far field 

    E-Print Network [OSTI]

    Sun, Qingqing; Al-Amri, M.; Scully, Marlan O.; Zubairy, M. Suhail.

    2011-01-01

    which we can obtain their distance and location information. This procedure also works for atomic separation above one wavelength and therefore provides a seamless microscopy....

  8. 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

  9. Open Source Scanning Probe Microscopy Control Software package GXSM

    SciTech Connect (OSTI)

    Zahl, P.; Wagner, T.; Moller, R.; Klust, A.

    2010-05-01

    GXSM is a full featured and modern scanning probe microscopy (SPM) software. It can be used for powerful multidimensional image/data processing, analysis, and visualization. Connected to an instrument, it is operating many different flavors of SPM, e.g., scanning tunneling microscopy and atomic force microscopy or, in general, two-dimensional multichannel data acquisition instruments. The GXSM core can handle different data types, e.g., integer and floating point numbers. An easily extendable plug-in architecture provides many image analysis and manipulation functions. A digital signal processor subsystem runs the feedback loop, generates the scanning signals, and acquires the data during SPM measurements. The programmable GXSM vector probe engine performs virtually any thinkable spectroscopy and manipulation task, such as scanning tunneling spectroscopy or tip formation. The GXSM software is released under the GNU general public license and can be obtained via the internet.

  10. 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...

  11. Detailed scanning probe microscopy tip models determined from simultaneous atom-resolved AFM and STM studies of the TiO2(110) surface

    E-Print Network [OSTI]

    Kühnle, Angelika

    scattering theory, we demonstrate how the state of the scanning probe microscopy SPM tip in the experiments may be determined. The analysis of a large number of experimental SPM images recorded with different-AFM and the tunneling current It images on TiO2 110 surface. The exact state of the SPM tip must, therefore

  12. Atomic-scale movement induced in nanoridges by scanning tunneling microscopy on epitaxial graphene grown on 4H-SiC(0001)

    E-Print Network [OSTI]

    Thibado, Paul M.

    in which forward and reverse images are simultaneously recorded. An apparent 100% enlarged graphene lattice of top- gated, electrically isolated devices, and furthermore, it is already available in the form tunneling microscopy (STM) studies have confirmed this interpretation and have shown that the large ridges

  13. Conductivity and structure of ErAs nanoparticles embedded in GaAs pn junctions analyzed via conductive atomic force microscopy

    E-Print Network [OSTI]

    Yu, Edward T.

    in III-V semiconductors J. Appl. Phys. 111, 103706 (2012) Role of surface trap states on two-dimensional electron gas density in InAlN/AlN/GaN heterostructures Appl. Phys. Lett. 100, 152116 (2012) Free carrier studies of macroscopic tunnel junctions. VC 2012 American Institute of Physics. [http://dx.doi.org/10

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

    E-Print Network [OSTI]

    Photosynthesis in plant cells is a ubiquitous natural solar energy conversion process. Light energy is captured (but also sulfate and nitrite reduction).1 This process is very similar to the energy process of solar developed in our laboratory for in situ sub-cellular probing of electrochemical phenomena in living plant

  15. Structural and electrical characterization of organic monolayers by Atomic Force Microscopy and through the nano-fabrication of a coplanar electrode-dielectric platform

    E-Print Network [OSTI]

    Martin, Florent

    2011-01-01

    deposition. Finally, electrical measurements are describedunderstanding of the electrical properties of ultra-thinsuch as the mobility of electrical carriers, the resistance

  16. Structural and electrical characterization of organic monolayers by Atomic Force Microscopy and through the nano-fabrication of a coplanar electrode-dielectric platform

    E-Print Network [OSTI]

    Martin, Florent

    2011-01-01

    freeware molecular editor Avogadro 11 . Figure 3-1. a AFMsimulations using the Avogadro freeware show that a bilayerfrom the freeware Avogadro 11 . Using this freeware, one can

  17. 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.

  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. Low-temperature evolution of local polarization properties of PbZr{sub 0.65}Ti{sub 0.35}O{sub 3} thin films probed by piezoresponse force microscopy

    SciTech Connect (OSTI)

    Andreeva, N. V.; Filimonov, A. V.; Rudskoy, A. I.; Tyunina, M.; Pertsev, N. A. Vakhrushev, S. B.

    2014-03-17

    The temperature evolution of local polarization properties in epitaxial PbZr{sub 0.65}Ti{sub 0.35}O{sub 3} films is studied by the low-temperature piezoresponse force microscopy (PFM). Pronounced changes in the film polarization state, including apparent polarization rotations and possible transitions between single-domain and polydomain states of individual ferroelectric nanocolumns, are revealed on cooling from the room temperature to 8?K using PFM imaging. More than two-fold increase in the coercive voltage extracted from the piezoresponse hysteresis loops is found on cooling from 240 to 8?K. The results are explained by the thermodynamic theory of strained epitaxial perovskite ferroelectric films.

  20. Nanoscale Electromechanics of Ferroelectric and Biological Systems: A New Dimension in Scanning Probe Microscopy

    SciTech Connect (OSTI)

    Kalinin, Sergei V [ORNL; Rodriguez, Brian J [ORNL; Jesse, Stephen [ORNL; Karapetian, Edgar [ORNL; Mirman, B [Suffolk University, Boston; Eliseev, E. A. [National Academy of Science of Ukraine, Kiev, Ukraine; Morozovska, A. N. [National Academy of Science of Ukraine, Kiev, Ukraine

    2007-01-01

    Functionality of biological and inorganic systems ranging from nonvolatile computer memories and microelectromechanical systems to electromotor proteins and cellular membranes is ultimately based on the intricate coupling between electrical and mechanical phenomena. In the past decade, piezoresponse force microscopy (PFM) has been established as a powerful tool for nanoscale imaging, spectroscopy, and manipulation of ferroelectric and piezoelectric materials. Here, we give an overview of the fundamental image formation mechanism in PFM and summarize recent theoretical and technological advances. In particular, we show that the signal formation in PFM is complementary to that in the scanning tunneling microscopy (STM) and atomic force microscopy (AFM) techniques, and we discuss the implications. We also consider the prospect of extending PFM beyond ferroelectric characterization for quantitative probing of electromechanical behavior in molecular and biological systems and high-resolution probing of static and dynamic polarization switching processes in low-dimensional ferroelectric materials and heterostructures.

  1. Dynamic Transmission Electron Microscopy

    SciTech Connect (OSTI)

    Evans, James E.; Jungjohann, K. L.; Browning, Nigel D.

    2012-10-12

    Dynamic transmission electron microscopy (DTEM) combines the benefits of high spatial resolution electron microscopy with the high temporal resolution of ultrafast lasers. The incorporation of these two components into a single instrument provides a perfect platform for in situ observations of material processes. However, previous DTEM applications have focused on observing structural changes occurring in samples exposed to high vacuum. Therefore, in order to expand the pump-probe experimental regime to more natural environmental conditions, in situ gas and liquid chambers must be coupled with Dynamic TEM. This chapter describes the current and future applications of in situ liquid DTEM to permit time-resolved atomic scale observations in an aqueous environment, Although this chapter focuses mostly on in situ liquid imaging, the same research potential exists for in situ gas experiments and the successful integration of these techniques promises new insights for understanding nanoparticle, catalyst and biological protein dynamics with unprecedented spatiotemporal resolution.

  2. 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

  3. Surface Preparation of Gallium Nitride for Atomic Layer Deposition of Aluminum Oxide /

    E-Print Network [OSTI]

    Kerr, Amanda J.

    2014-01-01

    Nitride for Atomic Layer Deposition of Aluminum Oxide AForce Microscopy Atomic Layer Deposition Capacitance-VoltageSurfaces for Atomic Layer Deposition of Aluminum Oxide” x

  4. [Band electronic structures and crystal packing forces]. Progress report, [March 1992--February 1993

    SciTech Connect (OSTI)

    Not Available

    1993-03-01

    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.

  5. Surface smoothing effect of an amorphous thin film deposited by atomic layer deposition on a surface with nano-sized roughness

    SciTech Connect (OSTI)

    Lau, W. S. Wan, X.; Xu, Y.; Wong, H.; Zhang, J.; Luo, J. K.; Institute of Renewable Energy and Environment Technology, Bolton University, Deane Road, Bolton BL3 5 AB

    2014-02-15

    Previously, Lau (one of the authors) pointed out that the deposition of an amorphous thin film by atomic layer deposition (ALD) on a substrate with nano-sized roughness probably has a surface smoothing effect. In this letter, polycrystalline zinc oxide deposited by ALD onto a smooth substrate was used as a substrate with nano-sized roughness. Atomic force microscopy (AFM) and cross-sectional transmission electron microscopy (XTEM) were used to demonstrate that an amorphous aluminum oxide thin film deposited by ALD can reduce the surface roughness of a polycrystalline zinc oxide coated substrate.

  6. Distance dependence of the phase signal in eddy current microscopy

    E-Print Network [OSTI]

    Roll, Tino; Fischer, Ulrich; Schleberger, Marika

    2008-01-01

    Atomic force microscopy using a magnetic tip is a promising tool for investigating conductivity on the nano-scale. By the oscillating magnetic tip eddy currents are induced in the conducting parts of the sample which can be detected in the phase signal of the cantilever. However, the origin of the phase signal is still controversial because theoretical calculations using a monopole appoximation for taking the electromagnetic forces acting on the tip into account yield an effect which is too small by more than two orders of magnitude. In order to determine the origin of the signal we used especially prepared gold nano patterns embedded in a non-conducting polycarbonate matrix and measured the distance dependence of the phase signal. Our data clearly shows that the interacting forces are long ranged and therefore, are likely due to the electromagnetic interaction between the magnetic tip and the conducting parts of the surface. Due to the long range character of the interaction a change in conductivity of $\\Del...

  7. 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.

  8. Ultrafast scanning tunneling microscopy

    SciTech Connect (OSTI)

    Botkin, D.A. [California Univ., Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley Lab., CA (United States)

    1995-09-01

    I have developed an ultrafast scanning tunneling microscope (USTM) based on uniting stroboscopic methods of ultrafast optics and scanned probe microscopy to obtain nanometer spatial resolution and sub-picosecond temporal resolution. USTM increases the achievable time resolution of a STM by more than 6 orders of magnitude; this should enable exploration of mesoscopic and nanometer size systems on time scales corresponding to the period or decay of fundamental excitations. USTM consists of a photoconductive switch with subpicosecond response time in series with the tip of a STM. An optical pulse from a modelocked laser activates the switch to create a gate for the tunneling current, while a second laser pulse on the sample initiates a dynamic process which affects the tunneling current. By sending a large sequence of identical pulse pairs and measuring the average tunnel current as a function of the relative time delay between the pulses in each pair, one can map the time evolution of the surface process. USTM was used to measure the broadband response of the STM`s atomic size tunnel barrier in frequencies from tens to hundreds of GHz. The USTM signal amplitude decays linearly with the tunnel junction conductance, so the spatial resolution of the time-resolved signal is comparable to that of a conventional STM. Geometrical capacitance of the junction does not appear to play an important role in the measurement, but a capacitive effect intimately related to tunneling contributes to the measured signals and may limit the ultimate resolution of the USTM.

  9. Functional photoacoustic microscopy 

    E-Print Network [OSTI]

    Zhang, Hao

    2009-06-02

    This dissertation focuses on laser-based noninvasive photoacoustic microscopy of subsurface structures in vivo. Photoacoustic microscopy is a hybrid imaging modality that combines the high-resolution advantage of ultrasonic imaging in deep tissue...

  10. 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

  11. E. Dan Dahlberg Magnetic Microscopy Center

    E-Print Network [OSTI]

    Dahlberg, E. Dan

    Coating Nanotube Bundle #12;Conventional EBD Topography Magnetism MFM Tip MFM Tip 1 µm Nickel Particles Beam Deposition (Spike) tips - Carbon Nanotube AFM/MFM tips High Resolution Magnetic Force Microscopy #12;Gonzo 500 nm #12;Carbon Nanotube MFM Uncoated Coated After Crash 300nm 6.7 µm 200 nm Multilayer

  12. Atomic layer deposition of zinc sulfide with Zn(TMHD){sub 2}

    SciTech Connect (OSTI)

    Short, Andrew; Jewell, Leila; Doshay, Sage; Church, Carena; Keiber, Trevor; Bridges, Frank; Carter, Sue; Alers, Glenn

    2013-01-15

    The atomic layer deposition (ALD) of ZnS films with Zn(TMHD){sub 2} and in situ generated H{sub 2}S as precursors was investigated, over a temperature range of 150-375 Degree-Sign C. ALD behavior was confirmed by investigation of growth behavior and saturation curves. The properties of the films were studied with atomic force microscopy, scanning electron microscopy, energy-dispersive x-ray spectroscopy, ultraviolet-visible-infrared spectroscopy, and extended x-ray absorption fine structure. The results demonstrate a film that can penetrate a porous matrix, with a local Zn structure of bulk ZnS, and a band gap between 3.5 and 3.6 eV. The ZnS film was used as a buffer layer in nanostructured PbS quantum dot solar cell devices.

  13. 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.

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

    E-Print Network [OSTI]

    Phillips, D.C.

    2006-01-01

    145 Uranyl Sorption on D.143 Uranyl sorption studies on D.TRLFS measurements of Uranyl Sorption onto D. radiodurans,

  15. VOLUME 76, NUMBER 8 P H Y S I C A L R E V I E W L E T T E R S 19 FEBRUARY 1996 Compliance Measurements of Confined Polystyrene Solutions by Atomic Force Microscopy

    E-Print Network [OSTI]

    . Pictroski,1 M. H. Rafailovich,2 Y. Liu,2 J. Quinn,2 J. Sokolov,2 A. Eisenberg,3 and G. Overney4 1 Exxon that when the lateral mobility is decreased quantitative confinement measurements with a nanometer contact whose lateral mobility is restricted by grafting one end to the solid substrate. This system is similar

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

    E-Print Network [OSTI]

    Phillips, D.C.

    2006-01-01

    W. ; Lu, C. in Applications of Piezoelectric Quartz CrystalW. ; Lu, C. in Applications of Piezoelectric Quartz Crystal

  17. Atomic Force Microscopy for materials research, modular easy upgrade to Confocal/Raman/SNOM www.WITec.de Refurbished Lab Equipment We sell quality refurbished lab equipment with warranty for less. www.marshallscientific.com

    E-Print Network [OSTI]

    Eldar, Yonina

    .WITec.de Refurbished Lab Equipment We sell quality refurbished lab equipment with warranty for less. www

  18. Nitride semiconductors studied by atom probe tomography and correlative techniques

    E-Print Network [OSTI]

    Bennett, Samantha

    2011-02-08

    , as well as atom probe tomography (APT), a technique more usually applied to metals that provides three-dimensional (3D) compositional information at the atomic scale. By using both APT and correlative microscopy techniques, a more complete understanding...

  19. Frontiers of in situ electron microscopy

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

    Zheng, Haimei; Zhu, Yimei; Meng, Shirley Ying

    2015-01-01

    In situ transmission electron microscopy (TEM) has become an increasingly important tool for materials characterization. It provides key information on the structural dynamics of a material during transformations and the correlation between structure and properties of materials. With the recent advances in instrumentation, including aberration corrected optics, sample environment control, the sample stage, and fast and sensitive data acquisition, in situ TEM characterization has become more and more powerful. In this article, a brief review of the current status and future opportunities of in situ TEM is included. It also provides an introduction to the six articles covered by inmore »this issue of MRS Bulletin explore the frontiers of in situ electron microscopy, including liquid and gas environmental TEM, dynamic four-dimensional TEM, nanomechanics, ferroelectric domain switching studied by in situ TEM, and state-of-the-art atomic imaging of light elements (i.e., carbon atoms) and individual defects.« less

  20. 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

  1. 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.

  2. Photothermal imaging scanning microscopy

    DOE Patents [OSTI]

    Chinn, Diane (Pleasanton, CA); Stolz, Christopher J. (Lathrop, CA); Wu, Zhouling (Pleasanton, CA); Huber, Robert (Discovery Bay, CA); Weinzapfel, Carolyn (Tracy, CA)

    2006-07-11

    Photothermal Imaging Scanning Microscopy produces a rapid, thermal-based, non-destructive characterization apparatus. Also, a photothermal characterization method of surface and subsurface features includes micron and nanoscale spatial resolution of meter-sized optical materials.

  3. Spectroscopic imaging in electron microscopy

    SciTech Connect (OSTI)

    Pennycook, Stephen J [ORNL; Colliex, C. [Universite Paris Sud, Orsay, France

    2012-01-01

    In the scanning transmission electron microscope, multiple signals can be simultaneously collected, including the transmitted and scattered electron signals (bright field and annular dark field or Z-contrast images), along with spectroscopic signals such as inelastically scattered electrons and emitted photons. In the last few years, the successful development of aberration correctors for the electron microscope has transformed the field of electron microscopy, opening up new possibilities for correlating structure to functionality. Aberration correction not only allows for enhanced structural resolution with incident probes into the sub-angstrom range, but can also provide greater probe currents to facilitate mapping of intrinsically weak spectroscopic signals at the nanoscale or even the atomic level. In this issue of MRS Bulletin, we illustrate the power of the new generation of electron microscopes with a combination of imaging and spectroscopy. We show the mapping of elemental distributions at atomic resolution and also the mapping of electronic and optical properties at unprecedented spatial resolution, with applications ranging from graphene to plasmonic nanostructures, and oxide interfaces to biology.

  4. Computational microscopy for sample analysis

    E-Print Network [OSTI]

    Ikoma, Hayato

    2014-01-01

    Computational microscopy is an emerging technology which extends the capabilities of optical microscopy with the help of computation. One of the notable example is super resolution fluorescence microscopy which achieves ...

  5. 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

  6. Nonlinear vibrational microscopy

    DOE Patents [OSTI]

    Holtom, Gary R. (Richland, WA); Xie, Xiaoliang Sunney (Richland, WA); Zumbusch, Andreas (Munchen, DE)

    2000-01-01

    The present invention is a method and apparatus for microscopic vibrational imaging using coherent Anti-Stokes Raman Scattering or Sum Frequency Generation. Microscopic imaging with a vibrational spectroscopic contrast is achieved by generating signals in a nonlinear optical process and spatially resolved detection of the signals. The spatial resolution is attained by minimizing the spot size of the optical interrogation beams on the sample. Minimizing the spot size relies upon a. directing at least two substantially co-axial laser beams (interrogation beams) through a microscope objective providing a focal spot on the sample; b. collecting a signal beam together with a residual beam from the at least two co-axial laser beams after passing through the sample; c. removing the residual beam; and d. detecting the signal beam thereby creating said pixel. The method has significantly higher spatial resolution then IR microscopy and higher sensitivity than spontaneous Raman microscopy with much lower average excitation powers. CARS and SFG microscopy does not rely on the presence of fluorophores, but retains the resolution and three-dimensional sectioning capability of confocal and two-photon fluorescence microscopy. Complementary to these techniques, CARS and SFG microscopy provides a contrast mechanism based on vibrational spectroscopy. This vibrational contrast mechanism, combined with an unprecedented high sensitivity at a tolerable laser power level, provides a new approach for microscopic investigations of chemical and biological samples.

  7. 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.

  8. 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

  9. 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

  10. Atomic-scale structural analyses of epitaxial Co/Re superlattices Wentao Xua)

    E-Print Network [OSTI]

    Pennycook, Steve

    2004) High-resolution transmission electron microscopy and scanning transmission electron microscopy-resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM) permit atomic superlattice samples were grown on 112¯0 Al2O3 substrates via dc magnetron sputtering with a base pressure of 3

  11. 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

  12. Ultrafast pump-probe force microscopy with nanoscale resolution

    E-Print Network [OSTI]

    2015-01-01

    Cerullo, “Confocal ultrafast pump-probe spectroscopy: A newand H. J. Maris, “Time-resolved pump-probe experiments withand U. Keller, “Femtosecond pump-porbe near-field optical

  13. Synthesis of multiferroic Er-Fe-O thin films by atomic layer and chemical vapor deposition

    SciTech Connect (OSTI)

    Mantovan, R., E-mail: roberto.mantovan@mdm.imm.cnr.it; Vangelista, S.; Wiemer, C.; Lamperti, A.; Tallarida, G. [Laboratorio MDM IMM-CNR, I-20864 Agrate Brianza (MB) (Italy); Chikoidze, E.; Dumont, Y. [GEMaC, Université de Versailles St. Quentin en Yvelines-CNRS, Versailles (France); Fanciulli, M. [Laboratorio MDM IMM-CNR, I-20864 Agrate Brianza (MB) (Italy); Dipartimento di Scienza dei Materiali, Università di Milano Bicocca, Milano (Italy)

    2014-05-07

    R-Fe-O (R?=?rare earth) compounds have recently attracted high interest as potential new multiferroic materials. Here, we report a method based on the solid-state reaction between Er{sub 2}O{sub 3} and Fe layers, respectively grown by atomic layer deposition and chemical vapor deposition, to synthesize Er-Fe-O thin films. The reaction is induced by thermal annealing and evolution of the formed phases is followed by in situ grazing incidence X-ray diffraction. Dominant ErFeO{sub 3} and ErFe{sub 2}O{sub 4} phases develop following subsequent thermal annealing processes at 850?°C in air and N{sub 2}. Structural, chemical, and morphological characterization of the layers are conducted through X-ray diffraction and reflectivity, time-of-flight secondary ion-mass spectrometry, and atomic force microscopy. Magnetic properties are evaluated by magnetic force microscopy, conversion electron Mössbauer spectroscopy, and vibrating sample magnetometer, being consistent with the presence of the phases identified by X-ray diffraction. Our results constitute a first step toward the use of cost-effective chemical methods for the synthesis of this class of multiferroic thin films.

  14. 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. ...

  15. Topography and refractometry of nanostructures using spatial light interference microscopy (SLIM)

    E-Print Network [OSTI]

    Gillette, Martha U.

    Topography and refractometry of nanostructures using spatial light interference microscopy (SLIM topography at a single atomic layer in graphene. Further, using a decoupling procedure that we developed high- throughput topography and refractometry of man-made and biological nanostructures. Quantitative

  16. Reinventing Pocket Microscopy

    E-Print Network [OSTI]

    Kamal, T; Lee, W M

    2015-01-01

    The key to the success of pocket microscopes stems from the convenience for anyone to magnify the fine details (tens of micrometres) of any object on-thespot. The capability with a portable microscope lets us surpass our limited vision and is commonly used in many areas of science, industry, education. The growth of imaging and computing power in smartphones is creating the possibility of converting your smartphone into a high power pocket microscope. In this article, we briefly describe the history of pocket microscopy and elucidate how mobile technologies are set to become the next platform for pocket microscopes

  17. Fourier plane imaging microscopy

    SciTech Connect (OSTI)

    Dominguez, Daniel, E-mail: daniel.dominguez@ttu.edu; Peralta, Luis Grave de [Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Nano Tech Center, Texas Tech University, Lubbock, Texas 79409 (United States); Alharbi, Nouf; Alhusain, Mdhaoui [Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Bernussi, Ayrton A. [Nano Tech Center, Texas Tech University, Lubbock, Texas 79409 (United States); Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States)

    2014-09-14

    We show how the image of an unresolved photonic crystal can be reconstructed using a single Fourier plane (FP) image obtained with a second camera that was added to a traditional compound microscope. We discuss how Fourier plane imaging microscopy is an application of a remarkable property of the obtained FP images: they contain more information about the photonic crystals than the images recorded by the camera commonly placed at the real plane of the microscope. We argue that the experimental results support the hypothesis that surface waves, contributing to enhanced resolution abilities, were optically excited in the studied photonic crystals.

  18. Characterization of Polymer Blends: Optical Microscopy (*Polarized, Interference and Phase Contrast Microscopy*) and Confocal Microscopy

    SciTech Connect (OSTI)

    Ramanathan, Nathan Muruganathan [ORNL; Darling, Seth B. [Argonne National Laboratory (ANL)

    2015-01-01

    Chapter 15 surveys the characterization of macro, micro and meso morphologies of polymer blends by optical microscopy. Confocal Microscopy offers the ability to view the three dimensional morphology of polymer blends, popular in characterization of biological systems. Confocal microscopy uses point illumination and a spatial pinhole to eliminate out-of focus light in samples that are thicker than the focal plane.

  19. Ultra-sensitive Magnetic Microscopy with an Atomic Magnetometer (Technical

    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 NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and(Conference) |Article) | SciTechArticle) |Report) | SciTech

  20. Ultra-sensitive Magnetic Microscopy with an Atomic Magnetometer (Technical

    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 NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and(Conference) |Article) | SciTechArticle) |Report) |

  1. SU P ER C O N D U C T O R S Imaging atomic-scale effects of high-energy ion

    E-Print Network [OSTI]

    Davis, James C.

    annihilated within the former and suppressed by the latter. Simultaneous atomically resolved images for suchmaterials engineering requires specific atomic-scale knowledge, in- cluding the structure of ion achieved by scanning tunneling microscopy (STM). However, to our knowledge, simultaneous atomic

  2. 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.

  3. Electrostrictive and electrostatic responses in contact mode voltage modulated Scanning Probe Microscopies

    SciTech Connect (OSTI)

    Eliseev, E. A.; Morozovska, A. N.; Ievlev, Anton; Balke, Nina; Maksymovych, Petro; Tselev, Alexander; Kalinin, Sergei V

    2014-01-01

    Electromechanical response of solids underpins image formation mechanism of several scanning probe microscopy techniques including the piezoresponse force microscopy (PFM) and electrochemical strain microscopy (ESM). While the theory of linear piezoelectric and ionic responses are well developed, the contributions of quadratic effects including electrostriction and capacitive tip-surface forces to measured signal remain poorly understood. Here we analyze the electrostrictive and capacitive contributions to the PFM and ESM signals and discuss the implications of the dielectric tip-surface gap on these interactions.

  4. 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?

  5. Single-layer MoS{sub 2} roughness and sliding friction quenching by interaction with atomically flat substrates

    SciTech Connect (OSTI)

    Quereda, J.; Castellanos-Gomez, A.; Agraït, N.; Rubio-Bollinger, G.

    2014-08-04

    We experimentally study the surface roughness and the lateral friction force in single-layer MoS{sub 2} crystals deposited on different substrates: SiO{sub 2}, mica, and hexagonal boron nitride (h-BN). Roughness and sliding friction measurements are performed by atomic force microscopy. We find a strong dependence of the MoS{sub 2} roughness on the underlying substrate material, being h-BN the substrate which better preserves the flatness of the MoS{sub 2} crystal. The lateral friction also lowers as the roughness decreases, and attains its lowest value for MoS{sub 2} flakes on h-BN substrates. However, it is still higher than for the surface of a bulk MoS{sub 2} crystal, which we attribute to the deformation of the flake due to competing tip-to-flake and flake-to-substrate interactions.

  6. 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

  7. 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.

  8. A national facility for biological cryo-electron microscopy

    SciTech Connect (OSTI)

    Saibil, Helen R.; Grünewald, Kay; Stuart, David I.

    2015-01-01

    This review provides a brief update on the use of cryo-electron microscopy for integrated structural biology, along with an overview of the plans for the UK national facility for electron microscopy being built at the Diamond synchrotron. Three-dimensional electron microscopy is an enormously powerful tool for structural biologists. It is now able to provide an understanding of the molecular machinery of cells, disease processes and the actions of pathogenic organisms from atomic detail through to the cellular context. However, cutting-edge research in this field requires very substantial resources for equipment, infrastructure and expertise. Here, a brief overview is provided of the plans for a UK national three-dimensional electron-microscopy facility for integrated structural biology to enable internationally leading research on the machinery of life. State-of-the-art equipment operated with expert support will be provided, optimized for both atomic-level single-particle analysis of purified macromolecules and complexes and for tomography of cell sections. The access to and organization of the facility will be modelled on the highly successful macromolecular crystallography (MX) synchrotron beamlines, and will be embedded at the Diamond Light Source, facilitating the development of user-friendly workflows providing near-real-time experimental feedback.

  9. 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.

  10. InGaAs surface preparation for atomic layer deposition by hydrogen cleaning and improvement with high temperature anneal

    E-Print Network [OSTI]

    Kummel, Andrew C.

    InGaAs surface preparation for atomic layer deposition by hydrogen cleaning and improvement channel III-V MOS devices can be fabricated with atomic layer deposition (ALD) high-K gate-first proc atomic scale imaging with scanning tunneling microscopy/spectroscopy, a combination of atomic hydrogen

  11. 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.

  12. 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,

  13. 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.

  14. 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

  15. 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.

  16. The future of electron microscopy

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

    Zhu, Yimei; Durr, Hermann

    2015-04-01

    Seeing is believing. So goes the old adage and seen evidence is undoubtedly satisfying because it can be interpreted easily, though not always correctly. For centuries, humans have developed such instruments as telescopes that observe the heavens and microscopes that reveal bacteria and viruses. The 2014 Nobel Prize in Chemistry was awarded to Eric Betzig, Stefan Hell, and William Moerner for their foundational work on superresolution fluorescence microscopy in which they overcame the Abbe diffraction limit for the resolving power of conventional light microscopes. (See Physics Today, December 2014, page 18.) That breakthrough enabled discoveries in biological research and testifiesmore »to the importance of modern microscopy.« less

  17. 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.

  18. Optimization of THz Microscopy Imaging

    E-Print Network [OSTI]

    Niessen, Katherine A

    2015-01-01

    THz near field microscopy opens a new frontier in material science. High spatial resolution requires the detection crystal to have uniform and reproducible response. We present the THz near field spatial and temporal response of ZnTe and GaP and examine possible properties that give rise to the ZnTe degraded signal.

  19. Holographic microscopy of holographically trapped

    E-Print Network [OSTI]

    Weeks, Eric R.

    . Padgett, "Permanent 3D microstructures in a polymeric host created using holographic optical tweezers," J to organize microscopic materials into three-dimensional structures. In a complementary manner, holographicHolographic microscopy of holographically trapped three-dimensional structures Sang-Hyuk Lee

  20. Atomic Scale Characterization of Compound Semiconductors using Atom Probe Tomography: Preprint

    SciTech Connect (OSTI)

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

    2011-07-01

    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.

  1. 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.

  2. Scanning standing-wave illumination microscopy : a path to nanometer resolution in X-ray microscopy

    E-Print Network [OSTI]

    Hong, Stanley Seokjong, 1977-

    2005-01-01

    X-ray microscopy can potentially combine the advantages of light microscopy with resolution approaching that of electron microscopy. In theory, x-ray microscopes can image unsectioned hydrated cells with nanometer resolution. ...

  3. Dynamic imaging with electron microscopy

    ScienceCinema (OSTI)

    Campbell, Geoffrey; McKeown, Joe; Santala, Melissa

    2014-05-30

    Livermore researchers have perfected an electron microscope to study fast-evolving material processes and chemical reactions. By applying engineering, microscopy, and laser expertise to the decades-old technology of electron microscopy, the dynamic transmission electron microscope (DTEM) team has developed a technique that can capture images of phenomena that are both very small and very fast. DTEM uses a precisely timed laser pulse to achieve a short but intense electron beam for imaging. When synchronized with a dynamic event in the microscope's field of view, DTEM allows scientists to record and measure material changes in action. A new movie-mode capability, which earned a 2013 R&D 100 Award from R&D Magazine, uses up to nine laser pulses to sequentially capture fast, irreversible, even one-of-a-kind material changes at the nanometer scale. DTEM projects are advancing basic and applied materials research, including such areas as nanostructure growth, phase transformations, and chemical reactions.

  4. 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

  5. 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

  6. Molecular-scale investigations of structures and surface charge distribution of surfactant aggregates by three-dimensional force mapping

    SciTech Connect (OSTI)

    Suzuki, Kazuhiro; Oyabu, Noriaki; Matsushige, Kazumi; Yamada, Hirofumi [Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510 (Japan)] [Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510 (Japan); Kobayashi, Kei [The Hakubi Center for Advanced Research, Kyoto University, Katsura, Nishikyo, Kyoto 615-8520 (Japan)] [The Hakubi Center for Advanced Research, Kyoto University, Katsura, Nishikyo, Kyoto 615-8520 (Japan)

    2014-02-07

    Surface charges on nanoscale structures in liquids, such as biomolecules and nano-micelles, play an essentially important role in their structural stability as well as their chemical activities. These structures interact with each other through electric double layers (EDLs) formed by the counter ions in electrolyte solution. Although static-mode atomic force microscopy (AFM) including colloidal-probe AFM is a powerful technique for surface charge density measurements and EDL analysis on a submicron scale in liquids, precise surface charge density analysis with single-nanometer resolution has not been made because of its limitation of the resolution and the detection sensitivity. Here we demonstrate molecular-scale surface charge measurements of self-assembled micellar structures, molecular hemicylinders of sodium dodecyl sulfate (SDS), by three-dimensional (3D) force mapping based on frequency modulation AFM. The SDS hemicylindrical structures with a diameter of 4.8 nm on a graphite surface were clearly imaged. We have succeeded in visualizing 3D EDL forces on the SDS hemicylinder surfaces and obtaining the molecular-scale charge density for the first time. The results showed that the surface charge on the trench regions between the hemicylinders was much smaller than that on the hemicylinder tops. The method can be applied to a wide variety of local charge distribution studies, such as spatial charge variation on a single protein molecule.

  7. 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.

  8. 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 ...

  9. 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.

  10. Visual-servoing optical microscopy

    SciTech Connect (OSTI)

    Callahan, Daniel E; Parvin, Bahram

    2013-10-01

    The present invention provides methods and devices for the knowledge-based discovery and optimization of differences between cell types. In particular, the present invention provides visual servoing optical microscopy, as well as analysis methods. The present invention provides means for the close monitoring of hundreds of individual, living cells over time; quantification of dynamic physiological responses in multiple channels; real-time digital image segmentation and analysis; intelligent, repetitive computer-applied cell stress and cell stimulation; and the ability to return to the same field of cells for long-term studies and observation. The present invention further provides means to optimize culture conditions for specific subpopulations of cells.

  11. Visual-servoing optical microscopy

    DOE Patents [OSTI]

    Callahan, Daniel E. (Martinez, CA); Parvin, Bahram (Mill Valley, CA)

    2011-05-24

    The present invention provides methods and devices for the knowledge-based discovery and optimization of differences between cell types. In particular, the present invention provides visual servoing optical microscopy, as well as analysis methods. The present invention provides means for the close monitoring of hundreds of individual, living cells over time; quantification of dynamic physiological responses in multiple channels; real-time digital image segmentation and analysis; intelligent, repetitive computer-applied cell stress and cell stimulation; and the ability to return to the same field of cells for long-term studies and observation. The present invention further provides means to optimize culture conditions for specific subpopulations of cells.

  12. Visual-servoing optical microscopy

    DOE Patents [OSTI]

    Callahan, Daniel E. (Martinez, CA); Parvin, Bahram (Hercules, CA)

    2009-06-09

    The present invention provides methods and devices for the knowledge-based discovery and optimization of differences between cell types. In particular, the present invention provides visual servoing optical microscopy, as well as analysis methods. The present invention provides means for the close monitoring of hundreds of individual, living cells over time: quantification of dynamic physiological responses in multiple channels; real-time digital image segmentation and analysis; intelligent, repetitive computer-applied cell stress and cell stimulation; and the ability to return to the same field of cells for long-term studies and observation. The present invention further provides means to optimize culture conditions for specific subpopulations of cells.

  13. Scanning near-field optical microscopy based on the heterodyne phase-controlled oscillator method

    E-Print Network [OSTI]

    Texas at Austin. University of

    Scanning near-field optical microscopy based on the heterodyne phase-controlled oscillator method G and quality factor of the tip oscillations was used to control the scanning near-field optical microscope SNOM and to study the nature of the shear-force interaction routinely used in SNOM. Both optical and nonoptical

  14. Physics PhD scholarship available in one the worlds top 10 cities Scanning Tunneling Microscopy studies of rare earth nitrides and related materials

    E-Print Network [OSTI]

    Hickman, Mark

    studies of rare earth nitrides and related materials This is an opportunity to explore how new rare earth nitride materials can be made and how they can be probed using scanning tunneling microscopy. Scanning Tunneling Microscopy is a powerful tool to obtain both atomic resolution imaging of the surface of materials

  15. 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

  16. 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.

  17. Frontiers of in situ electron microscopy

    SciTech Connect (OSTI)

    Zheng, Haimei; Zhu, Yimei; Meng, Shirley Ying

    2015-01-01

    In situ transmission electron microscopy (TEM) has become an increasingly important tool for materials characterization. It provides key information on the structural dynamics of a material during transformations and the correlation between structure and properties of materials. With the recent advances in instrumentation, including aberration corrected optics, sample environment control, the sample stage, and fast and sensitive data acquisition, in situ TEM characterization has become more and more powerful. In this article, a brief review of the current status and future opportunities of in situ TEM is included. It also provides an introduction to the six articles covered by in this issue of MRS Bulletin explore the frontiers of in situ electron microscopy, including liquid and gas environmental TEM, dynamic four-dimensional TEM, nanomechanics, ferroelectric domain switching studied by in situ TEM, and state-of-the-art atomic imaging of light elements (i.e., carbon atoms) and individual defects.

  18. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 14, NO. 1, JANUARY/FEBRUARY 2008 217 Spectral Self-Interference Fluorescence Microscopy

    E-Print Network [OSTI]

    resolution, we de- scribe and demonstrate a high-NA 4Pi microscopy system that per- forms spectral self of the Engineering Research Centers Program, in part by the Air Force Office of Scientific Research un- der Grant

  19. 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.

  20. 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.

  1. 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

  2. Ultra-High Resolution Electron Microscopy for Catalyst Characterizatio...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Documents & Publications Ultra-High Resolution Electron Microscopy for Catalyst Characterization Ultra-high Resolution Electron Microscopy for Catalyst Characterization...

  3. Communications Near-Field Fluorescence Microscopy of

    E-Print Network [OSTI]

    ** By Grace M. Credo and Steven K. Buratto* We use near-field scanning optical microscopy (NSOM) to probe. Buratto, G. M. Credo Department of Chemistry U

  4. Radiation-thermoacoustic microscopy of condensed media

    SciTech Connect (OSTI)

    Lyamshev, L.M.; Chelnokov, B.I.

    1984-07-01

    Possibilities are discussed for the application of scanning radiation-thermoacoustic microscopy, using different types of radiation, for microstructure analysis. (AIP)

  5. X-ray microscopy. Beyond ensemble averages

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

    Ice, Gene E.; Budai, John D.

    2015-06-23

    This work exemplifies emerging tools to characterize local materials structure and dynamics, made possible by powerful X-ray synchrotron and transmission electron microscopy methods.

  6. Combining Quantitative Electrochemistry and Electron Microscopy...

    Office of Scientific and Technical Information (OSTI)

    Combining Quantitative Electrochemistry and Electron Microscopy to Study Reversible Lithiation of Silicon Nanowires. Citation Details In-Document Search Title: Combining...

  7. ORNL microscopy directly images problematic lithium dendrites...

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

    images of the nucleation and growth of lithium dendrite structures known to degrade lithium-ion batteries. ORNL electron microscopy captured the first real-time nanoscale...

  8. Electron Microscopy Catalysis Projects: Success Stories from...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Catalysis Projects: Success Stories from the High Temperature Materials Laboratory (HTML) User Program Electron Microscopy Catalysis Projects: Success Stories from the High...

  9. 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.

  10. 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.

  11. 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.

  12. Local structures of high-entropy alloys (HEAs) on atomic scales: An overview

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

    Diao, Haoyan; Santodonato, Louis J.; Tang, Zhi; Egami, Takeshi; Liaw, Peter K.

    2015-08-29

    The high-entropy alloys, containing several elements mixed in equimolar or near-equimolar ratios, have shown exceptional engineering properties. Local structures on the atomic level are essential to understand the mechanical behaviors and related mechanisms. This article covers the local structure and stress on the atomic level are reviewed by the pair-distribution function of neutron-diffraction data, ab-initio molecular dynamics simulations, and the atomic probe microscopy.

  13. Scanning probe microscopy competency development

    SciTech Connect (OSTI)

    Hawley, M.E.; Reagor, D.W.; Jia, Quan Xi

    1998-12-31

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The project collaborators developed an ultra-high vacuum scanning tunneling microscope (UHV-STM) capability, integrated it with existing scanning probe microscopes, and developed new, advanced air-based scanning force techniques (SPMs). Programmatic, basic, and industrially related laboratory research requires the existence of SPMs, as well as expertise capable of providing local nano-scale information. The UHV-STM capability, equipped with load-lock system and several surface science techniques, will allow introduction, examination, and reaction of surfaces prepared under well-controlled vacuum conditions, including the examination of morphology and local bonding associated with the initial stages of film growth under controlled growth conditions. The resulting capabilities will enable the authors to respond to a variety of problems requiring local characterization of conducting and nonconducting surfaces in liquids, air, and UHV.

  14. 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...

  15. 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.

  16. Nonlinear Dark-Field Microscopy Hayk Harutyunyan,

    E-Print Network [OSTI]

    Novotny, Lukas

    /20/2010 Published on Web: 11/16/2010 FIGURE 1. Illustration of the nonlinear dark-field imaging method. Two incidentNonlinear Dark-Field Microscopy Hayk Harutyunyan, Stefano Palomba, Jan Renger, Romain Quidant Dark-field microscopy is a background-free imaging method that provides high sensitivity and a large

  17. 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.

  18. 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...

  19. 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.

  20. 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.

  1. 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.

  2. 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...

  3. Photoionization microscopy in terms of local frame transformation theory

    E-Print Network [OSTI]

    P. Giannakeas; F. Robicheaux; Chris H. Greene

    2014-10-27

    Two-photon ionization of an alkali-metal atom in the presence of a uniform electric field is investigated using a standardized form of local frame transformation and generalized quantum defect theory. The relevant long-range quantum defect parameters in the combined Coulombic plus Stark potential is calculated with eigenchannel R-matrix theory applied in the downstream parabolic coordinate $\\eta$. The present formulation permits us to express the corresponding microscopy observables in terms of the local frame transformation, and it gives a critical test of the accuracy of the Harmin-Fano theory permitting a scholastic investigation of the claims presented in Zhao {\\it et al.} [Phys. Rev. A 86, 053413 (2012)].

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. The application of Graphene as a sample support in Transmission Electron Microscopy

    E-Print Network [OSTI]

    Pantelic, R S; Kaiser, U; Stahlberg, H

    2012-01-01

    Transmission electron microscopy has witnessed rampant development and surging point resolution over the past few years. The improved imaging performance of modern electron microscopes shifts the bottleneck for image contrast and resolution to sample preparation. Hence, it is increasingly being realized that the full potential of electron microscopy will only be realized with the optimization of current sample preparation techniques. Perhaps the most recognized issues are background signal and noise contributed by sample supports, sample charging and instability. Graphene provides supports of single atom thickness, extreme physical stability, periodic structure, and ballistic electrical conductivity. As an increasing number of applications adapting graphene to their benefit emerge, we discuss the unique capabilities afforded by the use of graphene as a sample support for electron microscopy.

  9. 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.

  10. Spatially resolved quantitative mapping of thermomechanical properties and phase transition temperatures using scanning probe microscopy

    DOE Patents [OSTI]

    Jesse, Stephen; Kalinin, Sergei V; Nikiforov, Maxim P

    2013-07-09

    An approach for the thermomechanical characterization of phase transitions in polymeric materials (polyethyleneterephthalate) by band excitation acoustic force microscopy is developed. This methodology allows the independent measurement of resonance frequency, Q factor, and oscillation amplitude of a tip-surface contact area as a function of tip temperature, from which the thermal evolution of tip-surface spring constant and mechanical dissipation can be extracted. A heating protocol maintained a constant tip-surface contact area and constant contact force, thereby allowing for reproducible measurements and quantitative extraction of material properties including temperature dependence of indentation-based elastic and loss moduli.

  11. Dissecting the Molecular Basis of the Mechanics of Living Cells

    E-Print Network [OSTI]

    Kumar, Sanjay

    the past two decades, an exciting suite of sophisticated micro- and nanoscale technologies has emerged: atomic force microscopy, subcellular laser ablation, micropatterning, and microfluidics. Together biology. Keywords Cellular. Molecular. Structure . Mechanics . Atomic force microscopy. Laser

  12. 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.

  13. 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,...

  14. 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...

  15. Photon tunnelling microscopy of polyethylene single crystals

    E-Print Network [OSTI]

    Srinivasarao, Mohan

    Photon tunnelling microscopy of polyethylene single crystals Mohan Srinivasarao* and Richard S:photon tunnellingmicroscopy;single crystals; polyethylene) INTRODUCTION The study of morphology of polymers is an area

  16. Data visualization of biological microscopy image analyses

    E-Print Network [OSTI]

    Scelfo, Tony (Tony W.)

    2006-01-01

    The Open Microscopy Environment (OME) provides biologists with a framework to store, analyze and manipulate large sets of image data. Current microscopes are capable of generating large numbers of images and when coupled ...

  17. Chapter One Microscopy of Soft Materials

    E-Print Network [OSTI]

    Weeks, Eric R.

    . Shaving cream is a common example. · Sand, composed of large solid particles in vacuum, air, or a liquid of these soft systems are often com- patible with conventional video microscopy. For example, consider food

  18. High-resolution electron microscopy of advanced materials

    SciTech Connect (OSTI)

    Mitchell, T.E.; Kung, H.H.; Sickafus, K.E.; Gray, G.T. III; Field, R.D.; Smith, J.F.

    1997-11-01

    This final report chronicles a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The High-Resolution Electron Microscopy Facility has doubled in size and tripled in quality since the beginning of the three-year period. The facility now includes a field-emission scanning electron microscope, a 100 kV field-emission scanning transmission electron microscope (FE-STEM), a 300 kV field-emission high-resolution transmission electron microscope (FE-HRTEM), and a 300 kV analytical transmission electron microscope. A new orientation imaging microscope is being installed. X-ray energy dispersive spectrometers for chemical analysis are available on all four microscopes; parallel electron energy loss spectrometers are operational on the FE-STEM and FE-HRTEM. These systems enable evaluation of local atomic bonding, as well as chemical composition in nanometer-scale regions. The FE-HRTEM has a point-to-point resolution of 1.6 {angstrom}, but the resolution can be pushed to its information limit of 1 {angstrom} by computer reconstruction of a focal series of images. HRTEM has been used to image the atomic structure of defects such as dislocations, grain boundaries, and interfaces in a variety of materials from superconductors and ferroelectrics to structural ceramics and intermetallics.

  19. Ultra-high Resolution Electron Microscopy for Catalyst Characterizatio...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    high Resolution Electron Microscopy for Catalyst Characterization Ultra-high Resolution Electron Microscopy for Catalyst Characterization 2009 DOE Hydrogen Program and Vehicle...

  20. Ultra-High Resolution Electron Microscopy for Catalyst Characterizatio...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Documents & Publications Ultra-High Resolution Electron Microscopy for Catalyst Characterization Ultra-high Resolution Electron Microscopy for Catalyst Characterization Catalyst...

  1. Atomic-resolution study of Mn tetramer clusters using scanning tunneling Rong Yang, Haiqiang Yang, and Arthur R. Smitha

    E-Print Network [OSTI]

    Atomic-resolution study of Mn tetramer clusters using scanning tunneling microscopy Rong Yang clusters is investigated. The clusters are composed of a quadrant array of Mn atoms forming a tetramer of manganese nitride, on which are stabilized peri- odic, self-organized array of MnN-bonded Mn tetramer clus

  2. 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.

  3. Gas field ion source current stability for trimer and single atom terminated W(111) tips

    SciTech Connect (OSTI)

    Urban, Radovan; Wolkow, Robert A. [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2G7 (Canada); National Institute for Nanotechnology, National Research Council of Canada, Edmonton, Alberta T6G 2M9 (Canada); Pitters, Jason L. [National Institute for Nanotechnology, National Research Council of Canada, Edmonton, Alberta T6G 2M9 (Canada)

    2012-06-25

    Tungsten W(111) oriented trimer-terminated tips as well as single atom tips, fabricated by a gas and field assisted etching and evaporation process, were investigated with a view to scanning ion microscopy and ion beam writing applications. In particular, ion current stability was studied for helium and neon imaging gases. Large ion current fluctuations from individual atomic sites were observed when a trimer-terminated tip was used for the creation of neon ion beam. However, neon ion current was stable when a single atom tip was employed. No such current oscillations were observed for either a trimer or a single atom tip when imaged with helium.

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. Magnetic Force Microscopy Study of Zr2Co11 -Based Nanocrystalline Materials: Effect of Mo Addition

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

    Yue, Lanping; Jin, Yunlong; Zhang, Wenyong; Sellmyer, David J.

    2015-01-01

    The addition of Molybdenum was used to modify the nanostructure and enhance coercivity of rare-earth-free Zr2Co11-based nanocrystalline permanent magnets. The effect of Mo addition on magnetic domain structures of melt spun nanocrystalline Zr16Co84-xMox(x=0, 0.5, 1, 1.5, and 2.0) ribbons has been investigated. It was found that magnetic properties and local domain structures are strongly influenced by Mo doping. The coercivity of the samples increases with the increase in Mo content (x?1.5). The maximum energy product(BH)maxincreases with increasingxfrom 0.5?MGOe forx=0to a maximum value of 4.2?MGOe forx=1.5. The smallest domain size with a relativelymore »short magnetic correlation length of 128?nm and largest root-mean-square phase shift?rmsvalue of 0.66° are observed for thex=1.5. The optimal Mo addition promotes magnetic domain structure refinement and thus leads to a significant increase in coercivity and energy product in this sample.« less

  10. Force microscopy of layering and friction in an ionic liquid Judith Hotha,b

    E-Print Network [OSTI]

    Mueser, Martin

    in the contact were observed, resulting in multiple possible friction values for the same applied normal load-viscosity, yet load- bearing lubricant [1-4]. The load-bearing ability stems from the formation of solvation and sacrificial layer in a rubbing contact, in which lost material can get replenished quasi-instantly from

  11. A 4 K cryogenic probe for use in magnetic resonance force microscopy experiments

    SciTech Connect (OSTI)

    Smith, Doran D.; Alexson, Dimitri A. [U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland 20783 (United States)] [U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland 20783 (United States); Garbini, Joseph L. [Mechanical Engineering, University of Washington, Seattle, Washington 98195 (United States)] [Mechanical Engineering, University of Washington, Seattle, Washington 98195 (United States)

    2013-09-15

    The detailed design of a mechanically detected nuclear magnetic resonance probe using the SPAM (Springiness Preservation by Aligning Magnetization) geometry, operating at 4 K, in vacuum, and a several-Tesla magnetic field is described. The probe head is vibration-isolated well enough from the environment by a three-spring suspension system that the cantilever achieves thermal equilibrium with the environment without the aid of eddy current damping. The probe uses an ultra-soft Si cantilever with a Ni sphere attached to its tip, and magnetic resonance is registered as a change in the resonant frequency of the driven cantilever. The RF system uses frequency sweeps for adiabatic rapid passage using a 500 ?m diameter RF coil wound around a sapphire rod. The RF coil and optical fiber of the interferometer used to sense the cantilever's position are both located with respect to the cantilever using a Garbini micropositioner, and the sample stage is mounted on an Attocube nanopositioner.

  12. 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

  13. Materials Properties at Internal Interfaces: Fundamental Atomic Issues

    SciTech Connect (OSTI)

    Browning, Nigel

    2014-09-12

    During the course of this research, the microscopy methods were applied to many different systems (see publication list). However, the work can be broadly classified into three main areas: the statistical distribution of grain boundary structures under different doping conditions, the identification of individual dopant atoms in oxide materials, and the evaluation of nucleation and growth processes in liquid and more recently. The main results from each of these efforts will be discussed in the final report.

  14. Portable dual field gradient force multichannel flow cytometer device with a dual wavelength low noise detection scheme

    DOE Patents [OSTI]

    James, Conrad D; Galambos, Paul C; Derzon, Mark S; Graf, Darin C; Pohl, Kenneth R; Bourdon, Chris J

    2012-10-23

    Systems and methods for combining dielectrophoresis, magnetic forces, and hydrodynamic forces to manipulate particles in channels formed on top of an electrode substrate are discussed. A magnet placed in contact under the electrode substrate while particles are flowing within the channel above the electrode substrate allows these three forces to be balanced when the system is in operation. An optical detection scheme using near-confocal microscopy for simultaneously detecting two wavelengths of light emitted from the flowing particles is also discussed.

  15. 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.

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Meteoritic Nanodiamond Particles Studied by Atom-Probe Tomography D. Isheim*, J. B. Lewis**, D. N. Seidman*, T. L. Daulton**, F. J. Stadermann**, C. Floss**

    E-Print Network [OSTI]

    Floss, Christine

    Meteoritic Nanodiamond Particles Studied by Atom-Probe Tomography D. Isheim*, J. B. Lewis**, D. N nanodiamonds (NDs) with diamters of about 3 nm were first identified by transmission electron microscopy (TEM

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Four-wave mixing microscopy of nanostructures

    E-Print Network [OSTI]

    Potma, Eric Olaf

    Four-wave mixing microscopy of nanostructures Yong Wang, Chia-Yu Lin, Alexei Nikolaenko, Varun July 14, 2010; accepted July 27, 2010; published September 10, 2010 (Doc. ID 128079) The basics of four-wave. Four-Wave Mixing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2

  10. Femtosecond Optical Spectroscopy and Scanning Probe Microscopy

    E-Print Network [OSTI]

    Scherer, Norbert F.

    microscopy (FOS-SPM), is capable of spatial localization of optically induced phenomenon at intdaces. Spatially localized, time resolved spectroscopicmeasurements are achieved via couplingof the metal SPM tip to an optical field at the interhqe.[2,3] FOS-SPM has been shown to be capable of identqing and differentating

  11. 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.

  12. 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.

  13. 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)

  14. Tools for macromolecular model building and refinement into electron cryo-microscopy reconstructions

    SciTech Connect (OSTI)

    Brown, Alan; Long, Fei; Nicholls, Robert A.; Toots, Jaan; Emsley, Paul; Murshudov, Garib, E-mail: garib@mrc-lmb.cam.ac.uk [MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH (United Kingdom)

    2015-01-01

    A description is given of new tools to facilitate model building and refinement into electron cryo-microscopy reconstructions. The recent rapid development of single-particle electron cryo-microscopy (cryo-EM) now allows structures to be solved by this method at resolutions close to 3 Å. Here, a number of tools to facilitate the interpretation of EM reconstructions with stereochemically reasonable all-atom models are described. The BALBES database has been repurposed as a tool for identifying protein folds from density maps. Modifications to Coot, including new Jiggle Fit and morphing tools and improved handling of nucleic acids, enhance its functionality for interpreting EM maps. REFMAC has been modified for optimal fitting of atomic models into EM maps. As external structural information can enhance the reliability of the derived atomic models, stabilize refinement and reduce overfitting, ProSMART has been extended to generate interatomic distance restraints from nucleic acid reference structures, and a new tool, LIBG, has been developed to generate nucleic acid base-pair and parallel-plane restraints. Furthermore, restraint generation has been integrated with visualization and editing in Coot, and these restraints have been applied to both real-space refinement in Coot and reciprocal-space refinement in REFMAC.

  15. 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

  16. Atomic-scale and three-dimensional transmission electron microscopy of nanoparticle morphology

    E-Print Network [OSTI]

    Leary, Rowan Kendall

    2015-02-03

    Nicoletti and Cate Ducati, as well as Marc Amrbrüster and his co-workers. I also thank Rik Brydson and colleagues for their ongoing encouragement, and for inviting me back to the University of Leeds each year to lecture on electron tomography at the Royal...

  17. Application of Surface Spectroscopies and Microscopies to Elucidate Sorption Mechanisms on Oxide Surfaces

    E-Print Network [OSTI]

    Sparks, Donald L.

    -resolution transmission electron microscopy (HRTEM), and surface probing microscopy (SPM) were used to discern

  18. 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.

  19. 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.

  20. Low-temperature atomic layer deposition of Al{sub 2}O{sub 3} on blown polyethylene films with plasma-treated surfaces

    SciTech Connect (OSTI)

    Beom Lee, Gyeong; Sik Son, Kyung; Won Park, Suk; Hyung Shim, Joon; Choi, Byoung-Ho

    2013-01-15

    In this study, a layer of Al{sub 2}O{sub 3} was deposited on blown polyethylene films by atomic layer deposition (ALD) at low temperatures, and the surface characteristics of these Al{sub 2}O{sub 3}-coated blown polyethylene films were analyzed. In order to examine the effects of the plasma treatment of the surfaces of the blown polyethylene films on the properties of the films, both untreated and plasma-treated film samples were prepared under various processing conditions. The surface characteristics of the samples were determined by x-ray photoelectron spectroscopy, as well as by measuring their surface contact angles. It was confirmed that the surfaces of the plasma-treated samples contained a hydroxyl group, which helped the precursor and the polyethylene substrate to bind. ALD of Al{sub 2}O{sub 3} was performed through sequential exposures to trimethylaluminum and H{sub 2}O at 60 Degree-Sign C. The surface morphologies of the Al{sub 2}O{sub 3}-coated blown polyethylene films were observed using atomic force microscopy and scanning electron microscopy/energy-dispersive x-ray spectroscopy. Further, it was confirmed that after ALD, the surface of the plasma-treated film was covered with alumina grains more uniformly than was the case for the surface of the untreated polymer film. It was also confirmed via the focused ion beam technique that the layer Al{sub 2}O{sub 3} conformed to the surface of the blown polyethylene film.

  1. 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.

  2. 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...

  3. New Developments in Transmission Electron Microscopy for Nanotechnology**

    E-Print Network [OSTI]

    Wang, Zhong L.

    New Developments in Transmission Electron Microscopy for Nanotechnology** By Zhong Lin Wang* 1. Electron Microscopy and Nanotechnology Nanotechnology, as an international initiative for science manufacturing are the foundation of nanotechnology. Tracking the historical background of why nanotechnology

  4. In-Situ Electron Microscopy of Electrical Energy Storage Materials...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    es095unocic2011o.pdf More Documents & Publications In-Situ Electron Microscopy of Electrical Energy Storage Materials In-Situ Electron Microscopy of Electrical Energy Storage...

  5. In-Situ Electron Microscopy of Electrical Energy Storage Materials...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    es095unocic2012p.pdf More Documents & Publications In-Situ Electron Microscopy of Electrical Energy Storage Materials In-Situ Electron Microscopy of Electrical Energy Storage...

  6. Record-Setting Microscopy Illuminates Energy Storage Materials

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

    Record-Setting Microscopy Illuminates Energy Storage Materials Print X-ray microscopy is powerful in that it can probe large volumes of material at high spatial resolution with...

  7. 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.

  8. 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

  9. Chemically-selective imaging of brain structures with CARS microscopy

    E-Print Network [OSTI]

    Xie, Xiaoliang Sunney

    Chemically-selective imaging of brain structures with CARS microscopy Conor L. Evans1§ , Xiaoyin Xu anti-Stokes Raman scattering (CARS) microscopy to image brain structure and pathology ex vivo. Although. Definitive diagnosis still requires brain biopsy in a significant number of cases. CARS microscopy

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Studying The Kinetics Of Crystalline Silicon Nanoparticle Lithiation With In-Situ Transmission Electron Microscopy

    SciTech Connect (OSTI)

    Mcdowell, Matthew T.; Ryu, Ill; Lee, Seokwoo; Wang, Chong M.; Nix, William D.; Cui, Yi

    2012-11-27

    Silicon is an attractive high-capacity anode material for Li-ion batteries, but a comprehensive understanding of the massive ~300% volume change and fracture during lithiation/delithiation is necessary to reliably employ Si anodes. Here, in-situ transmission electron microscopy (TEM) of the lithiation of crystalline Si nanoparticles reveals that the reaction slows down as it progresses into the particle interior. Analysis suggests that this behavior is due to the influence of mechanical stress at the reaction front on the driving force for the reaction. These experiments give insight into the factors controlling the kinetics of this unique reaction.

  15. Sub-microsecond-resolution probe microscopy

    DOE Patents [OSTI]

    Ginger, David; Giridharagopal, Rajiv; Moore, David; Rayermann, Glennis; Reid, Obadiah

    2014-04-01

    Methods and apparatus are provided herein for time-resolved analysis of the effect of a perturbation (e.g., a light or voltage pulse) on a sample. By operating in the time domain, the provided method enables sub-microsecond time-resolved measurement of transient, or time-varying, forces acting on a cantilever.

  16. 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.

  17. 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

  18. 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.

  19. Fast electron microscopy via compressive sensing

    DOE Patents [OSTI]

    Larson, Kurt W; Anderson, Hyrum S; Wheeler, Jason W

    2014-12-09

    Various technologies described herein pertain to compressive sensing electron microscopy. A compressive sensing electron microscope includes a multi-beam generator and a detector. The multi-beam generator emits a sequence of electron patterns over time. Each of the electron patterns can include a plurality of electron beams, where the plurality of electron beams is configured to impart a spatially varying electron density on a sample. Further, the spatially varying electron density varies between each of the electron patterns in the sequence. Moreover, the detector collects signals respectively corresponding to interactions between the sample and each of the electron patterns in the sequence.

  20. New Microscopy Patent Awarded | The Ames Laboratory

    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 Home Room NewsInformationJessework usesofPublications64 2.251 2.211 2.196 2.172companies atNew Microscopy

  1. 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.

  2. Integrating atomic layer deposition and ultra-high vacuum physical vapor deposition for in situ fabrication of tunnel junctions

    SciTech Connect (OSTI)

    Elliot, Alan J., E-mail: alane@ku.edu, E-mail: jwu@ku.edu; Malek, Gary A.; Lu, Rongtao; Han, Siyuan; Wu, Judy Z., E-mail: alane@ku.edu, E-mail: jwu@ku.edu [Department of Physics and Astronomy, The University of Kansas, Lawrence, Kansas 66045 (United States); Yu, Haifeng; Zhao, Shiping [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-07-15

    Atomic Layer Deposition (ALD) is a promising technique for growing ultrathin, pristine dielectrics on metal substrates, which is essential to many electronic devices. Tunnel junctions are an excellent example which require a leak-free, ultrathin dielectric tunnel barrier of typical thickness around 1 nm between two metal electrodes. A challenge in the development of ultrathin dielectric tunnel barriers using ALD is controlling the nucleation of dielectrics on metals with minimal formation of native oxides at the metal surface for high-quality interfaces between the tunnel barrier and metal electrodes. This poses a critical need for integrating ALD with ultra-high vacuum (UHV) physical vapor deposition. In order to address these challenges, a viscous-flow ALD chamber was designed and interfaced to an UHV magnetron sputtering chamber via a load lock. A sample transportation system was implemented for in situ sample transfer between the ALD, load lock, and sputtering chambers. Using this integrated ALD-UHV sputtering system, superconductor-insulator-superconductor (SIS) Nb-Al/Al{sub 2}O{sub 2}/Nb Josephson tunnel junctions were fabricated with tunnel barriers of thickness varied from sub-nm to ?1 nm. The suitability of using an Al wetting layer for initiation of the ALD Al{sub 2}O{sub 3} tunnel barrier was investigated with ellipsometry, atomic force microscopy, and electrical transport measurements. With optimized processing conditions, leak-free SIS tunnel junctions were obtained, demonstrating the viability of this integrated ALD-UHV sputtering system for the fabrication of tunnel junctions and devices comprised of metal-dielectric-metal multilayers.

  3. 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 ...

  4. 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.

  5. 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.

  6. Thermal expansion recovery microscopy: Practical design considerations

    SciTech Connect (OSTI)

    Mingolo, N. Martínez, O. E.

    2014-01-15

    A detailed study of relevant parameters for the design and operation of a photothermal microscope technique recently introduced is presented. The technique, named thermal expansion recovery microscopy (ThERM) relies in the measurement of the defocusing introduced by a surface that expands and recovers upon the heating from a modulated source. A new two lens design is presented that can be easily adapted to commercial infinite conjugate microscopes and the sensitivity to misalignment is analyzed. The way to determine the beam size by means of a focus scan and the use of that same scan to verify if a thermoreflectance signal is overlapping with the desired ThERM mechanism are discussed. Finally, a method to cancel the thermoreflectance signal by an adequate choice of a nanometric coating is presented.

  7. Cell shape identification using digital holographic microscopy

    E-Print Network [OSTI]

    Zakrisson, Johan; Andersson, Magnus

    2015-01-01

    We present a cost-effective, simple and fast digital holographic microscopy method based upon Rayleigh-Sommerfeld back propagation for identification of the geometrical shape of a cell. The method was tested using synthetic hologram images generated by ray-tracing software and from experimental images of semi-transparent spherical beads and living red blood cells. Our results show that by only using the real part of the back-reconstructed amplitude the proposed method can provide information of the geometrical shape of the object and at the same time accurately determine the axial position of the object under study. The proposed method can be used in flow chamber assays for pathophysiological studies where fast morphological changes of cells are studied in high numbers and at different heights.

  8. Multifunctional Composites and Devices for Sensing and Energy Harvesting 

    E-Print Network [OSTI]

    Cleveland, Michael Allen

    2011-08-08

    melting method, the magenetocaloric samples were created. Multi-length scales characterized using atomic force microscopy (AFM), optical microscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), X-Ray diffraction (XRD...

  9. Thin polymer films of block copolymers and blend/nanoparticle composites 

    E-Print Network [OSTI]

    Kalloudis, Michail

    2013-11-28

    In this thesis, atomic force microscopy (AFM), transmission electron microscopy (TEM) and optical microscopy techniques were used to investigate systematically the self-assembled nanostructure behaviour of two different ...

  10. Electrohydrodynamic atomization (EHDA) assisted wet chemical synthesis of nickel nanoparticles

    SciTech Connect (OSTI)

    Barzegar Vishlaghi, M. [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)] [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of); Farzalipour Tabriz, M., E-mail: meisam.fa@gmail.com [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of); Mohammad Moradi, O. [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)] [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2012-07-15

    Highlights: ? Electrohydrodynamic atomization (EHDA) assisted chemical synthesis of nickel nanoparticles is reported. ? Substituting water with non-aqueous media prevents the formation of nickel hydroxide. ? Size of particles decreased from 10 to 20 nm down to 2–4 nm by using multi-jet mode. ? Synthesized nanoparticles have diffraction patterns similar to amorphous materials. -- Abstract: In this study nickel nanoparticles were prepared via chemical reduction of nickel acetate using sodium borohydride using electrohydrodynamic atomization (EHDA) technique. This technique was used to spray a finely dispersed aerosol of nickel precursor solution into the reductive bath. Obtained particles were characterized by means of X-ray diffraction (XRD), UV–Visible spectroscopy, and transmission electron microscopy (TEM). Results confirmed the formation of nickel nanoparticles and showed that applying EHDA technique to chemical reduction method results in producing smaller particles with narrower size distribution in comparison with conventional reductive precipitation method.

  11. Direct visualization of atomically precise nitrogen-doped graphene nanoribbons

    SciTech Connect (OSTI)

    Zhang, Yi; Zhang, Yanfang; Li, Geng; Lu, Jianchen; Du, Shixuan, E-mail: sxdu@iphy.ac.cn, E-mail: feng@mpip-mainz.mpg.de; Gao, Hong-Jun [Institute of Physics and University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190 (China); Lin, Xiao [University of Chinese Academy of Sciences and Institute of Physics, Chinese Academy of Sciences, Beijing 100049 (China); Berger, Reinhard; Feng, Xinliang, E-mail: sxdu@iphy.ac.cn, E-mail: feng@mpip-mainz.mpg.de; Müllen, Klaus [Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz (Germany)

    2014-07-14

    We have fabricated atomically precise nitrogen-doped chevron-type graphene nanoribbons by using the on-surface synthesis technique combined with the nitrogen substitution of the precursors. Scanning tunneling microscopy and spectroscopy indicate that the well-defined nanoribbons tend to align with the neighbors side-by-side with a band gap of 1.02?eV, which is in good agreement with the density functional theory calculation result. The influence of the high precursor coverage on the quality of the nanoribbons is also studied. We find that graphene nanoribbons with sufficient aspect ratios can only be fabricated at sub-monolayer precursor coverage. This work provides a way to construct atomically precise nitrogen-doped graphene nanoribbons.

  12. Programming new geometry restraints: Parallelity of atomic groups

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

    Sobolev, Oleg V.; Afonine, Pavel V.; Adams, Paul D.; Urzhumtsev, Alexandre

    2015-08-01

    Improvements in structural biology methods, in particular crystallography and cryo-electron microscopy, have created an increased demand for the refinement of atomic models against low-resolution experimental data. One way to compensate for the lack of high-resolution experimental data is to use a priori information about model geometry that can be utilized in refinement in the form of stereochemical restraints or constraints. Here, the definition and calculation of the restraints that can be imposed on planar atomic groups, in particular the angle between such groups, are described. Detailed derivations of the restraint targets and their gradients are provided so that they canmore »be readily implemented in other contexts. Practical implementations of the restraints, and of associated data structures, in the Computational Crystallography Toolbox(cctbx) are presented.« less

  13. 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...

  14. 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...

  15. 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.

  16. 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

  17. 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.

  18. Reactivity of Ozone with Solid Potassium Iodide Investigated by Atomic

    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 NaturalDukeWakefieldSulfateSciTech ConnectSpeedingConnect PulseSummary (ProgrambatteriesLi-Force Microscopy (Journal

  19. Reactivity of Ozone with Solid Potassium Iodide Investigated by Atomic

    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 NaturalDukeWakefieldSulfateSciTech ConnectSpeedingConnect PulseSummary (ProgrambatteriesLi-Force Microscopy

  20. Dynamics of Cell Shape and Forces on Micropatterned Substrates Predicted by a Cellular Potts Model

    E-Print Network [OSTI]

    Philipp J. Albert; Ulrich S. Schwarz

    2014-05-19

    Micropatterned substrates are often used to standardize cell experiments and to quantitatively study the relation between cell shape and function. Moreover, they are increasingly used in combination with traction force microscopy on soft elastic substrates. To predict the dynamics and steady states of cell shape and forces without any a priori knowledge of how the cell will spread on a given micropattern, here we extend earlier formulations of the two-dimensional cellular Potts model. The third dimension is treated as an area reservoir for spreading. To account for local contour reinforcement by peripheral bundles, we augment the cellular Potts model by elements of the tension-elasticity model. We first parameterize our model and show that it accounts for momentum conservation. We then demonstrate that it is in good agreement with experimental data for shape, spreading dynamics, and traction force patterns of cells on micropatterned substrates. We finally predict shapes and forces for micropatterns that have not yet been experimentally studied.

  1. X-Ray Microscopy Reveals How Crystal Mechanics Drive Battery...

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

    Microscopy Reveals How Crystal Mechanics Drive Battery Performance Print Rechargeable lithium-ion batteries power most portable electronics and are becoming more widely used in...

  2. In situ transmission electron microscopy investigation of the...

    Office of Scientific and Technical Information (OSTI)

    In situ transmission electron microscopy investigation of the interfacial reaction between Ni and Al during rapid heating in a nanocalorimeter Grapes, Michael D. Department of...

  3. In situ transmission electron microscopy investigation of the...

    Office of Scientific and Technical Information (OSTI)

    Published Article: In situ transmission electron microscopy investigation of the interfacial reaction between Ni and Al during rapid heating in a nanocalorimeter Title: In situ...

  4. Los Alamos: MST: MST-6: EML: Electron Microscopy Laboratory

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

    is also greater flexibility in choice of standards and ZAF correction schemes. Digital Mapping and Imaging. Automated Stage capable of 1 micron steps. Geller Microscopy Wavelength...

  5. "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

  6. Atomic-scale electrochemistry on the surface of a manganite

    SciTech Connect (OSTI)

    Vasudevan, Rama K; Tselev, Alexander; Baddorf, Arthur P; Kalinin, Sergei V

    2015-01-01

    The doped manganese oxides (manganites) have been widely studied for their colossal magnetoresistive effects, for potential applications in oxide spintronics, electroforming in resistive switching devices, and are materials of choice as cathodes in modern solid oxide fuel cells. However, little experimental knowledge of the dynamics of the surfaces of perovskite manganites at the atomic scale exists. Here, through in-situ scanning tunnelling microscopy (STM), we demonstrate atomic resolution on samples of La0.625Ca0.375MnO3 grown on (001) SrTiO3 by pulsed laser deposition (PLD). Furthermore, by applying triangular DC waveforms of increasing amplitude to the STM tip, and measuring the tunnelling current, we demonstrate the ability to both perform and monitor surface electrochemical processes at the atomic level, including, for the first time in a manganite, formation of single and multiple oxygen vacancies, disruption of the overlying manganite layers, and removal and deposition of individual atomic units or clusters. Our work paves the way for better understanding of surface oxygen reactions in these systems.

  7. 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

  8. Direct imaging of crystal structure and defects in metastable Ge{sub 2}Sb{sub 2}Te{sub 5} by quantitative aberration-corrected scanning transmission electron microscopy

    SciTech Connect (OSTI)

    Ross, Ulrich; Lotnyk, Andriy Thelander, Erik; Rauschenbach, Bernd

    2014-03-24

    Knowledge about the atomic structure and vacancy distribution in phase change materials is of foremost importance in order to understand the underlying mechanism of fast reversible phase transformation. In this Letter, by combining state-of-the-art aberration-corrected scanning transmission electron microscopy with image simulations, we are able to map the local atomic structure and composition of a textured metastable Ge{sub 2}Sb{sub 2}Te{sub 5} thin film deposited by pulsed laser deposition with excellent spatial resolution. The atomic-resolution scanning transmission electron microscopy investigations display the heterogeneous defect structure of the Ge{sub 2}Sb{sub 2}Te{sub 5} phase. The obtained results are discussed. Highly oriented Ge{sub 2}Sb{sub 2}Te{sub 5} thin films appear to be a promising approach for further atomic-resolution investigations of the phase change behavior of this material class.

  9. 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.

  10. 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.

  11. 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 ...

  12. 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.

  13. Ion-induced electron emission microscopy

    DOE Patents [OSTI]

    Doyle, Barney L. (Albuquerque, NM); Vizkelethy, Gyorgy (Albuquerque, NM); Weller, Robert A. (Brentwood, TN)

    2001-01-01

    An ion beam analysis system that creates multidimensional 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 secondary electrons emitted at that point with a signal from a detector that measures the interaction of that ion within the sample. The emitted secondary electrons are collected in a strong electric field perpendicular to the sample surface and (optionally) projected and refocused by the electron lenses found in a photon emission electron microscope, amplified by microchannel plates and then their exact position is sensed by a very sensitive X Y position detector. Position signals from this secondary electron detector are then correlated in time with nuclear, atomic or electrical effects, including the malfunction of digital circuits, detected within the sample that were caused by the individual ion that created these secondary electrons in the fit place.

  14. 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. .

  15. 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.

  16. 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.

  17. 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.

  18. Complete information acquisition in scanning probe microscopy

    SciTech Connect (OSTI)

    Belianinov, Alex [ORNL; Kalinin, Sergei V [ORNL; Jesse, Stephen [ORNL

    2015-01-01

    In the last three decades, scanning probe microscopy (SPM) has emerged as a primary tool for exploring and controlling the nanoworld. A critical part of the SPM measurements is the information transfer from the tip-surface junction to a macroscopic measurement system. This process reduces the many degrees of freedom of a vibrating cantilever to relatively few parameters recorded as images. Similarly, the details of dynamic cantilever response at sub-microsecond time scales of transients, higher-order eigenmodes and harmonics are averaged out by transitioning to millisecond time scale of pixel acquisition. Hence, the amount of information available to the external observer is severely limited, and its selection is biased by the chosen data processing method. Here, we report a fundamentally new approach for SPM imaging based on information theory-type analysis of the data stream from the detector. This approach allows full exploration of complex tip-surface interactions, spatial mapping of multidimensional variability of material s properties and their mutual interactions, and SPM imaging at the information channel capacity limit.

  19. Atomically-resolved mapping of polarization and electric fields across ferroelectric-oxide interfaces by Z-contrast imaging

    SciTech Connect (OSTI)

    Chang, Hye Jung; Kalinin, Sergei; Morozovska, A. N.; Huijben, Mark; Chu, Ying-Hao; Yu, P; Ramesh, R.; Eliseev, E. A.; Svechnikov, S. V.; Pennycook, Stephen J; Borisevich, Albina Y

    2011-01-01

    Direct atomic displacement mapping at ferroelectric interfaces by aberration corrected scanning transmission electron microscopy(STEM) (a-STEM image, b-corresponding displacement profile) is combined with Landau-Ginsburg-Devonshire theory to obtain the complete interface electrostatics in real space, including separate estimates for the polarization and intrinsic interface charge contributions.

  20. High precision stereo profilometry

    E-Print Network [OSTI]

    Aumond, Bernardo Dantas, 1972-

    2001-01-01

    Metrological data from sample surfaces can be obtained by using a variety of profilome try methods. Atomic Force Microscopy (AFM), which relies on contact inter-atomic forces to extract topographical images of a sample, ...

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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)

  11. 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

  12. Near-field microwave microscopy of high-? oxides grown on graphene with an organic seeding layer

    SciTech Connect (OSTI)

    Tselev, Alexander Kalinin, Sergei V.; Sangwan, Vinod K.; Jariwala, Deep; Lauhon, Lincoln J.; Marks, Tobin J.; Hersam, Mark C.; Department of Chemistry, Northwestern University, Evanston, Illinois 60208

    2013-12-09

    Near-field scanning microwave microscopy (SMM) is used for non-destructive nanoscale characterization of Al{sub 2}O{sub 3} and HfO{sub 2} films grown on epitaxial graphene on SiC by atomic layer deposition using a self-assembled perylene-3,4,9,10-tetracarboxylic dianhydride seeding layer. SMM allows imaging of buried inhomogeneities in the dielectric layer with a spatial resolution close to 100?nm. The results indicate that, while topographic features on the substrate surface cannot be eliminated as possible sites of defect nucleation, the use of a vertically heterogeneous Al{sub 2}O{sub 3}/HfO{sub 2} stack suppresses formation of large outgrowth defects in the oxide film, ultimately improving lateral uniformity of the dielectric film.

  13. Hetero-epitaxial EuO interfaces studied by analytic electron microscopy

    SciTech Connect (OSTI)

    Mundy, Julia A.; Hodash, Daniel; Melville, Alexander; Held, Rainer; Mairoser, Thomas; Schmehl, Andreas; Muller, David A.; Kourkoutis, Lena F.; Schlom, Darrell G.

    2014-03-03

    With nearly complete spin polarization, the ferromagnetic semiconductor europium monoxide could enable next-generation spintronic devices by providing efficient ohmic spin injection into silicon. Spin injection is greatly affected by the quality of the interface between the injector and silicon. Here, we use atomic-resolution scanning transmission electron microscopy in conjunction with electron energy loss spectroscopy to directly image and chemically characterize a series of EuO|Si and EuO|YAlO{sub 3} interfaces fabricated using different growth conditions. We identify the presence of europium silicides and regions of disorder at the EuO|Si interfaces, imperfections that could significantly reduce spin injection efficiencies via spin-flip scattering.

  14. High-resolution ab initio three-dimensional x-ray diffraction microscopy

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

    Chapman, Henry N.; Barty, Anton; Marchesini, Stefano; Noy, Aleksandr; Hau-Riege, Stefan P.; Cui, Congwu; Howells, Malcolm R.; Rosen, Rachel; He, Haifeng; Spence, John C. H.; et al

    2006-01-01

    Coherent x-ray diffraction microscopy is a method of imaging nonperiodic isolated objects at resolutions limited, in principle, by only the wavelength and largest scattering angles recorded. We demonstrate x-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the three-dimensional diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a nonperiodic object. We also construct two-dimensional images of thick objects with greatly increased depth of focus (without loss of transverse spatialmore »resolution). These methods can be used to image biological and materials science samples at high resolution with x-ray undulator radiation and establishes the techniques to be used in atomic-resolution ultrafast imaging at x-ray free-electron laser sources.« less

  15. 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

  16. 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

  17. 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).

  18. 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...

  19. 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

  20. 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

  1. 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...

  2. Largely defocused probe scanning transmission electron microscopy for imaging local modulation of strain field in a hetero interface

    SciTech Connect (OSTI)

    Kim, Suhyun Jung, Younheum; Kim, Joong Jung; Lee, Sunyoung; Lee, Haebum; Oshima, Yoshifumi

    2014-10-13

    We present an innovative method for characterizing the strain field in three dimensions in a hetero interface. Largely defocused probe scanning transmission electron microscopy (LDP-STEM) was employed for imaging the inhomogeneous strain field in a germanium (Ge) layer deposited on a silicon (Si) substrate. In the LDP-STEM image, Ge-atomic columns that are relaxed or strained to the Si substrate in the Si/Ge hetero interface were observed to be distinguishable, allowing for the qualitative characterization of the coherency of the crystal growth. Our results revealed that the strain field is locally modulated along the in-plane direction in the Si/Ge hetero interface.

  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. Thickness determination of few-layer hexagonal boron nitride films by scanning electron microscopy and Auger electron spectroscopy

    SciTech Connect (OSTI)

    Sutter, P. Sutter, E.

    2014-09-01

    We assess scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) for thickness measurements on few-layer hexagonal boron nitride (h-BN), the layered dielectric of choice for integration with graphene and other two-dimensional materials. Observations on h-BN islands with large, atomically flat terraces show that the secondary electron intensity in SEM reflects monolayer height changes in films up to least 10 atomic layers thickness. From a quantitative analysis of AES data, the energy-dependent electron escape depth in h-BN films is deduced. The results show that AES is suitable for absolute thickness measurements of few-layer h-BN of 1 to 6 layers.

  6. Mapping Ionic Currents and Reactivity on the Nanoscale: Electrochemical Strain Microscopy

    SciTech Connect (OSTI)

    Kalinin, S.V. (Center for Nanophase Materials Sciences, ORNL) [Center for Nanophase Materials Sciences, ORNL

    2010-10-19

    Solid-state electrochemical processes in oxides underpin a broad spectrum of energy and information storage devices, ranging from Li-ion and Li-air batteries, to solid oxide fuel cells (SOFC) to electroresistive and memristive systems. These functionalities are controlled by the bias-driven diffusive and electromigration transport of mobile ionic species, as well as intricate a set of electrochemical and defect-controlled reactions at interfaces and in bulk. Despite the wealth of device-level and atomistic studies, little is known on the mesoscopic mechanisms of ion diffusion and electronic transport on the level of grain clusters, individual grains, and extended defects. The development of the capability for probing ion transport on the nanometer scale is a key to deciphering complex interplay between structure, functionality, and performance in these systems. Here we introduce Electrochemical Strain Microscopy, a scanning probe microscopy technique based on strong strain-bias coupling in the systems in which local ion concentrations are changed by electrical fields. The imaging capability, as well as time- and voltage spectroscopies analogous to traditional current based electrochemical characterization methods are developed. The reversible intercalation of Li and mapping electrochemical activity in LiCoO2 is demonstrated, illustrating higher Li diffusivity at non-basal planes and grain boundaries. In Si-anode device structure, the direct mapping of Li diffusion at extended defects and evolution of Li-activity with charge state is explored. The electrical field-dependence of Li mobility is studied to determine the critical bias required for the onset of electrochemical transformation, allowing reaction and diffusion processes in the battery system to be separated at each location. Finally, the applicability of ESM for probing oxygen vacancy diffusion and oxygen reduction/evolution reactions is illustrated, and the high resolution ESM maps are correlated with aberration corrected scanning transmission electron microscopy imaging. The future potential for deciphering mechanisms of electrochemical transformations on an atomically-defined single-defect level is discussed.

  7. 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

  8. 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

  9. 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)

  10. 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.

  11. 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.

  12. 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.

  13. Degradation of Staphylococcus aureus bacteria by neutral oxygen atoms

    SciTech Connect (OSTI)

    Cvelbar, U.; Mozetic, M. [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Hauptman, N.; Klanjsek-Gunde, M. [National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana (Slovenia)

    2009-11-15

    The degradation of Staphylococcus aureus bacteria during treatment with neutral oxygen atoms was monitored by scanning electron microscopy. Experiments were performed in an afterglow chamber made from borosilicate glass. The source of oxygen atoms was remote inductively coupled radiofrequency oxygen plasma. The density of atoms at the samples was 8x10{sup 20} m{sup -3}. The treatment was performed at room temperature. The first effect was the removal of dried capsule. Capsule on exposed parts of bacteria was removed after receiving the dose of 6x10{sup 23} at./m{sup 2}, while the parts of capsule filling the gaps between bacteria were removed after receiving the dose of 2.4x10{sup 24} m{sup -2}. After removing the capsule, degradation continued as etching of bacterial cell wall. The etching was rather nonuniform as holes with diameter of several 10 nm were observed. The cell wall was removed after receiving the dose of about 7x10{sup 24} m{sup -2}. The etching probabilities were about 2x10{sup -5} for the capsule and 2x10{sup -6} for the cell wall. The results were explained by different compositions of capsule and the cell wall.

  14. 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.

  15. 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.

  16. X-Ray Diffraction Microscopy of Magnetic Structures

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

    X-Ray Diffraction Microscopy of Magnetic Structures Print science brief icon Scientists working at ALS Beamline 12.0.2.2 have demonstrated a new x-ray technique for producing...

  17. Carmichael's Concise Review Microscopy is Only Skin Deep

    E-Print Network [OSTI]

    Heller, Eric

    Carmichael's Concise Review Microscopy is Only Skin Deep Stephen W. Carmichael Mayo Clinic. Coming Events 2011 EMAS 2011 May 15­19, 2011 Angers, France www.emas-web.net IUMAS-V May 22­27, 2011

  18. Imaging chromophores with undetectable fluorescence by stimulated emission microscopy

    E-Print Network [OSTI]

    Xie, Xiaoliang Sunney

    LETTERS Imaging chromophores with undetectable fluorescence by stimulated emission microscopy Wei, that is, spontaneous emission, is generally more sensitive than absorption measurement, and is widely used undetectable fluorescence because the spontaneous emission is dominated by theirfastnon-radiative decay3

  19. Classifying and Segmenting Microscopy Images Using Convolutional Multiple Instance Learning

    E-Print Network [OSTI]

    Oren Z. Kraus; Lei Jimmy Ba; Brendan Frey

    2015-11-17

    Convolutional neural networks (CNN) have achieved state of the art performance on both classification and segmentation tasks. Applying CNNs to microscopy images is challenging due to the lack of datasets labeled at the single cell level. We extend the application of CNNs to microscopy image classification and segmentation using multiple instance learning (MIL). We present the adaptive Noisy-AND MIL pooling function, a new MIL operator that is robust to outliers. Combining CNNs with MIL enables training CNNs using full resolution microscopy images with global labels. We base our approach on the similarity between the aggregation function used in MIL and pooling layers used in CNNs. We show that training MIL CNNs end-to-end outperforms several previous methods on both mammalian and yeast microscopy images without requiring any segmentation steps.

  20. Optical fiber based ultrashort pulse multispectral nonlinear optical microscopy 

    E-Print Network [OSTI]

    Larson, Adam Michael

    2009-05-15

    Nonlinear optical microscopy (NLOM) utilizing femtosecond laser pulses is well suited for imaging living tissues. This work reports on the design and development of an optical fiber based multispectral NLOM developed around ...

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Combined confocal Raman and quantitative phase microscopy system for biomedical diagnosis

    E-Print Network [OSTI]

    Kang, Jeon Woong

    We have developed a novel multimodal microscopy system that incorporates confocal Raman, confocal reflectance, and quantitative phase microscopy (QPM) into a single imaging entity. Confocal Raman microscopy provides detailed ...

  6. Transmission electron microscopy characterization of Zircaloy-4 and ZIRLOTM oxide layers

    E-Print Network [OSTI]

    Motta, Arthur T.

    Transmission electron microscopy characterization of Zircaloy-4 and ZIRLOTM oxide layers Benoit de, and archived before and after the transition, are characterized using transmission electron microscopy improvement. Results obtained from transmission electron microscopy (TEM) samples archived just before

  7. 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 ...

  8. 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.

  9. Swept source optical coherence microscopy for pathological assessment of cancerous tissues

    E-Print Network [OSTI]

    Ahsen, Osman Oguz

    2013-01-01

    Optical coherence microscopy (OCM) combines optical coherence tomography (OCT) with confocal microscopy and enables depth resolved visualization of biological specimens with cellular resolution. OCM offers a suitable ...

  10. 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.

  11. 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...

  12. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    atomic force microscopy (1) availability (1) beetles (1) chemical vapor deposition (1) chemistry (1) Filter by Author Hemminger, John C. (9) Liu, Yu (5) Brown, Matthew A. (4)...

  13. Local characterization of hindered Brownian motion by using digital video microscopy and 3D particle tracking

    E-Print Network [OSTI]

    Simon L Dettmer; Ulrich F Keyser; Stefano Pagliara

    2014-08-19

    In this article we present methods for measuring hindered Brownian motion in the confinement of complex 3D geometries using digital video microscopy. Here we discuss essential features of automated 3D particle tracking as well as diffusion data analysis. By introducing local mean squared displacement-vs-time curves, we are able to simultaneously measure the spatial dependence of diffusion coefficients, tracking accuracies and drift velocities. Such local measurements allow a more detailed and appropriate description of strongly heterogeneous systems as opposed to global measurements. Finite size effects of the tracking region on measuring mean squared displacements are also discussed. The use of these methods was crucial for the measurement of the diffusive behavior of spherical polystyrene particles (505 nm diameter) in a microfluidic chip. The particles explored an array of parallel channels with different cross sections as well as the bulk reservoirs. For this experiment we present the measurement of local tracking accuracies in all three axial directions as well as the diffusivity parallel to the channel axis while we observed no significant flow but purely Brownian motion. Finally, the presented algorithm is suitable also for tracking of fluorescently labeled particles and particles driven by an external force, e.g. electrokinetic or dielectrophoretic forces.

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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...

  5. 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

  6. 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

  7. 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.

  8. 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...

  9. 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.

  10. 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

  11. 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...

  12. Imaging hydrated microbial extracellular polymers: Comparative analysis by electron microscopy

    SciTech Connect (OSTI)

    Dohnalkova, A.C.; Marshall, M. J.; Arey, B. W.; Williams, K. H.; Buck, E. C.; Fredrickson, J. K.

    2011-01-01

    Microbe-mineral and -metal interactions represent a major intersection between the biosphere and geosphere but require high-resolution imaging and analytical tools for investigating microscale associations. Electron microscopy has been used extensively for geomicrobial investigations and although used bona fide, the traditional methods of sample preparation do not preserve the native morphology of microbiological components, especially extracellular polymers. Herein, we present a direct comparative analysis of microbial interactions using conventional electron microscopy approaches of imaging at room temperature and a suite of cryogenic electron microscopy methods providing imaging in the close-to-natural hydrated state. In situ, we observed an irreversible transformation of the hydrated bacterial extracellular polymers during the traditional dehydration-based sample preparation that resulted in their collapse into filamentous structures. Dehydration-induced polymer collapse can lead to inaccurate spatial relationships and hence could subsequently affect conclusions regarding nature of interactions between microbial extracellular polymers and their environment.

  13. Atomic Layer Deposition of ZnO on Multi-walled Carbon Nanotubes and Its Use for Synthesis of CNT–ZnO Heterostructures

    E-Print Network [OSTI]

    2010-08-07

    Abstract In this article, direct coating of ZnO on PECVD-grown multi-walled carbon nanotubes (MWCNTs) is achieved using atomic layer deposition (ALD). Transmission electron microscopy investigation shows that the deposited ZnO shell is continuous...

  14. Formation of ion-irradiation-induced atomic-scale defects on walls of carbon nanotubes A. V. Krasheninnikov,1,2

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Formation of ion-irradiation-induced atomic-scale defects on walls of carbon nanotubes A. V Recent experiments on irradiated carbon nanotubes provide evidence that ion bombardment gives rise tunneling microscopy STM images of irradiated nanotubes. We demonstrate that irradiation-induced defects may

  15. Study of Interactions Between Microbes and Minerals by Scanning Transmission X-Ray Microscopy (STXM)

    E-Print Network [OSTI]

    Benzerara, K; Tyliszczak, T

    2007-01-01

    Study of Interactions Between Microbes and Minerals by Scanning Transmission X-Ray Microscopy (STXM)

  16. Scanning Transmission X-ray Microscopy: Applications in Atmospheric Aerosol Research

    E-Print Network [OSTI]

    Moffet, Ryan C.

    2011-01-01

    polymer photoresists by scanning transmission x-ray microscopy. Journal of Vacuum Science and Technology

  17. Variable temperature electrochemical strain microscopy of Sm-doped ceria

    SciTech Connect (OSTI)

    Jesse, Stephen; Morozovska, A. N.; Kalinin, Sergei V; Eliseev, E. A.; Yang, Nan; Doria, Sandra; Tebano, Antonello

    2013-01-01

    Variable temperature electrochemical strain microscopy has been used to study the electrochemical activity of Sm-doped ceria as a function of temperature and bias. The electrochemical strain microscopy hysteresis loops have been collected across the surface at different temperatures and the relative activity at different temperatures has been compared. The relaxation behavior of the signal at different temperatures has been also evaluated to relate kinetic process during bias induced electrochemical reactions with temperature and two different kinetic regimes have been identified. The strongly non-monotonic dependence of relaxation behavior on temperature is interpreted as evidence for water-mediated mechanisms.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. Preparation of Samples for Light Microscopy Simple Wax Seal

    E-Print Network [OSTI]

    Fygenson, Deborah Kuchnir

    Preparation of Samples for Light Microscopy Simple Wax Seal Materials - Slide - Cover Slip - Paraffin Wax Candle - Pasteur Pipette (suggested size 5 3/4 inch) - Matches Preparation of the Slide - You may want to protect the work surface from melted wax. We use a sheet of aluminum foil taped

  4. Radio-frequency scanning tunnelling microscopy U. Kemiktarak1

    E-Print Network [OSTI]

    LETTERS Radio-frequency scanning tunnelling microscopy U. Kemiktarak1 , T. Ndukum3 , K. C. Schwab3 measurementsinmesoscopicelectronicsandmechanics. Broadband noise measurements across the tunnel junction using this radio-frequency STM available from nanoscale optical and electrical displacement detection tech- niques, and the radio

  5. Instrument Series: Microscopy Ultra-High Vacuum, Low-

    E-Print Network [OSTI]

    Instrument Series: Microscopy Ultra-High Vacuum, Low- Temperature Scanning Probe Microscope EMSL's ultra-high vacuum, low-temperature scanning probe microscope instrument, or UHV LT SPM range of surface analytical techniques at low temperature ­ enables ultra-violet/X-ray photoelectron

  6. Transient photoinduced diffractive solid immersion lens for infrared microscopy

    E-Print Network [OSTI]

    Palanker, Daniel

    plate structure on the surfaces of semiconductor wafers with high indices of refraction. Lenses properties were determined. We demonstrate that transient SILs can have lifetimes longer than 50 ps microscopy. A solid immersion lens SIL focuses radiation within a material of a high re- fractive index

  7. Visualizing Individual Carbon Nanotubes with Optical Microscopy Michael A. Novak,

    E-Print Network [OSTI]

    with Ag or TiO2 nanocrystals.21,22 Although this approach is high throughput, the deposited materialVisualizing Individual Carbon Nanotubes with Optical Microscopy Michael A. Novak, Sumedh Surwade carbon nanotubes (CNTs) on a silicon wafer using a conventional optical microscope. We show

  8. POLYMER IMAGING WITH FRESNEL PROJECTION MICROSCOPY VU THIEN BINH1

    E-Print Network [OSTI]

    Peters, Achim

    1 POLYMER IMAGING WITH FRESNEL PROJECTION MICROSCOPY VU THIEN BINH1 , V. SEMET1 and N. GARCIA2 1 exploited in a compact low-energy electron microscope: the Fresnel Projection Microscope. Images size of the sources. The result is a high-resolution, low-energy electron microscope, the "Fresnel

  9. Optimal resolution in Fresnel incoherent correlation holographic fluorescence microscopy

    E-Print Network [OSTI]

    Rosen, Joseph

    Optimal resolution in Fresnel incoherent correlation holographic fluorescence microscopy Gary, Israel 4 rosen@ee.bgu.ac.il *gbrooker@jhu.edu Abstract: Fresnel Incoherent Correlation Holography (FINCH. Rosen and G. Brooker, "Digital spatially incoherent Fresnel holography," Opt. Lett. 32(8), 912­914 (2007

  10. An investigation of receiver probe development for magnetic resonance microscopy 

    E-Print Network [OSTI]

    Boyer, Jeffrey Scott

    1995-01-01

    . The objective of the research presented in this thesis is to extend the analysis and design of conventional RF coil systems to that for MR microscopy. Specifically, distinctions in terms of signal and noise are made between conventional RF coils and coils...

  11. 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.

  12. 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...

  13. 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;...

  14. 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.

  15. Adhesion and Atomic Structures of Gold on Ceria Nanostructures:The Role of Surface Structure and Oxidation State of Ceria Supports

    SciTech Connect (OSTI)

    Lin, Yuyuan [Northwestern University, Evanston; Wu, Zili [ORNL; Wen, Jianguo [Argonne National Laboratory (ANL); Poeppelmeier, Kenneth R [Northwestern University, Evanston; Marks, Laurence D [Northwestern University, Evanston

    2015-01-01

    Recent advances in heterogeneous catalysis have demonstrated that oxides supports with the same material but different shapes can result in metal catalysts with distinct catalytic properties. The shape-dependent catalysis was not well-understood owing to the lack of direct visualization of the atomic structures at metal-oxide interface. Herein, we utilized aberration-corrected electron microscopy and revealed the atomic structures of gold particles deposited on ceria nanocubes and nanorods with {100} or {111} facets exposed. For the ceria nanocube support, gold nanoparticles have extended atom layers at the metal-support interface. In contrast, regular gold nanoparticles and rafts are present on the ceria nanorod support. After hours of water gas shift reaction, the extended gold atom layers and rafts vanish, which is associated with the decrease of the catalytic activities. By understanding the atomic structures of the support surfaces, metal-support interfaces, and morphologies of the gold particles, a direct structure-property relationship is established.

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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...