National Library of Energy BETA

Sample records for magic angle spinning

  1. High-resolution NMR spectroscopy of biological tissues usingprojected Magic Angle Spinning

    SciTech Connect (OSTI)

    Martin, Rachel W.; Jachmann, Rebecca C.; Sakellariou, Dimitris; Nielsen, Ulla Gro; Pines, Alexander

    2005-01-27

    High-resolution NMR spectra of materials subject toanisotropic broadening are usually obtained by rotating the sample aboutthe magic angle, which is 54.7 degrees to the static magnetic field. Inprojected Magic Angle Spinning (p-MAS), the sample is spun about twoangles, neither of which is the magic angle. This provides a method ofobtaining isotropic spectra while spinning at shallow angles. The p-MASexperiment may be used in situations where spinning the sample at themagic angle is not possible due to geometric or other constraints,allowing the choice of spinning angle to be determined by factors such asthe shape of the sample, rather than by the spin physics. The applicationof this technique to bovine tissue samples is demonstrated as a proof ofprinciple for future biological or medical applications.

  2. Sealed magic angle spinning nuclear magnetic resonance probe and process for spectroscopy of hazardous samples

    DOE Patents [OSTI]

    Cho, Herman M.; Washton, Nancy M.; Mueller, Karl T.; Sears, Jr., Jesse A.; Townsend, Mark R.; Ewing, James R.

    2016-06-14

    A magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) probe is described that includes double containment enclosures configured to seal and contain hazardous samples for analysis. The probe is of a modular design that ensures containment of hazardous samples during sample analysis while preserving spin speeds for superior NMR performance and convenience of operation.

  3. Devices and process for high-pressure magic angle spinning nuclear magnetic resonance

    DOE Patents [OSTI]

    Hoyt, David W; Sears, Jr., Jesse A; Turcu, Romulus V.F.; Rosso, Kevin M; Hu, Jian Zhi

    2014-04-08

    A high-pressure magic angle spinning (MAS) rotor is detailed that includes a high-pressure sample cell that maintains high pressures exceeding 150 bar. The sample cell design minimizes pressure losses due to penetration over an extended period of time.

  4. Magic angle spinning nuclear magnetic resonance apparatus and process for high-resolution in situ investigations

    SciTech Connect (OSTI)

    Hu, Jian Zhi; Sears, Jr., Jesse A.; Hoyt, David W.; Mehta, Hardeep S.; Peden, Charles H. F.

    2015-11-24

    A continuous-flow (CF) magic angle sample spinning (CF-MAS) NMR rotor and probe are described for investigating reaction dynamics, stable intermediates/transition states, and mechanisms of catalytic reactions in situ. The rotor includes a sample chamber of a flow-through design with a large sample volume that delivers a flow of reactants through a catalyst bed contained within the sample cell allowing in-situ investigations of reactants and products. Flow through the sample chamber improves diffusion of reactants and products through the catalyst. The large volume of the sample chamber enhances sensitivity permitting in situ .sup.13C CF-MAS studies at natural abundance.

  5. Advanced slow-magic angle spinning probe for magnetic resonance imaging and spectroscopy

    DOE Patents [OSTI]

    Wind, Robert A.; Hu, Jian Zhi; Minard, Kevin R.; Rommereim, Donald N.

    2006-01-24

    The present invention relates to a probe and processes useful for magnetic resonance imaging and spectroscopy instruments. More particularly, the invention relates to a MR probe and processes for obtaining resolution enhancements of fluid objects, including live specimens, using an ultra-slow (magic angle) spinning (MAS) of the specimen combined with a modified phase-corrected magic angle turning (PHORMAT) pulse sequence. Proton NMR spectra were measured of the torso and the top part of the belly of a female BALBc mouse in a 2T field, while spinning the animal at a speed of 1.5 Hz. Results show that even in this relatively low field with PHORMAT, an isotropic spectrum is obtained with line widths that are a factor 4.6 smaller than those obtained in a stationary mouse. Resolution of 1H NMR metabolite spectra are thus significantly enhanced. Results indicate that PHORMAT has the potential to significantly increase the utility of 1H NMR spectroscopy for in vivo biochemical, biomedical and/or medical applications involving large-sized biological objects such as mice, rats and even humans within a hospital setting. For small-sized objects, including biological objects, such as excised tissues, organs, live bacterial cells, and biofilms, use of PASS at a spinning rate of 30 Hz and above is preferred.

  6. Magnetic resonance imaging of DNP enhancements in a rotor spinning at the magic angle

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

    Perras, Frederic A.; Kobayashi, Takeshi; Pruski, Marek

    2016-02-23

    Simulations performed on model, static, samples have shown that the microwave power is non-uniformly distributed in the magic angle spinning (MAS) rotor when using conventional dynamic nuclear polarization (DNP) instrumentation. Here, we applied the stray-field magic angle spinning imaging (STRAFI–MAS) experiment to generate a spatial map of the DNP enhancements in a full rotor, which is spun at a low rate in a commercial DNP–MAS NMR system. Notably, we observed that the enhancement factors produced in the center of the rotor can be twice as large as those produced at the top of the rotor. Surprisingly, we observed that themore » largest enhancement factors are observed along the axis of the rotor as opposed to against its walls, which are most directly irradiated by the microwave beam. We lastly observed that the distribution of enhancement factors can be moderately improved by degassing the sample and increasing the microwave power. The inclusion of dielectric particles greatly amplifies the enhancement factors throughout the rotor. Furthermore, the STRAFI–MAS approach can provide useful guidance for optimizing the access of microwave power to the sample, and thereby lead to further increases in sensitivity of DNP–MAS NMR.« less

  7. A unified heteronuclear decoupling strategy for magic-angle-spinning solid-state NMR spectroscopy

    SciTech Connect (OSTI)

    Equbal, Asif; Bjerring, Morten; Nielsen, Niels Chr. E-mail: ncn@inano.au.dk; Madhu, P. K. E-mail: ncn@inano.au.dk

    2015-05-14

    A unified strategy of two-pulse based heteronuclear decoupling for solid-state magic-angle spinning nuclear magnetic resonance is presented. The analysis presented here shows that different decoupling sequences like two-pulse phase-modulation (TPPM), X-inverse-X (XiX), and finite pulse refocused continuous wave (rCW{sup A}) are basically specific solutions of a more generalized decoupling scheme which incorporates the concept of time-modulation along with phase-modulation. A plethora of other good decoupling conditions apart from the standard, TPPM, XiX, and rCW{sup A} decoupling conditions are available from the unified decoupling approach. The importance of combined time- and phase-modulation in order to achieve the best decoupling conditions is delineated. The consequences of different indirect dipolar interactions arising from cross terms comprising of heteronuclear and homonuclear dipolar coupling terms and also those between heteronuclear dipolar coupling and chemical-shift anisotropy terms are presented in order to unfold the effects of anisotropic interactions under different decoupling conditions. Extensive numerical simulation results are corroborated with experiments on standard amino acids.

  8. High-pressure, high-temperature magic angle spinning nuclear magnetic resonance devices and processes for making and using same

    SciTech Connect (OSTI)

    Hu, Jian Zhi; Hu, Mary Y.; Townsend, Mark R.; Lercher, Johannes A.; Peden, Charles H. F.

    2015-10-06

    Re-usable ceramic magic angle spinning (MAS) NMR rotors constructed of high-mechanic strength ceramics are detailed that include a sample compartment that maintains high pressures up to at least about 200 atmospheres (atm) and high temperatures up to about least about 300.degree. C. during operation. The rotor designs minimize pressure losses stemming from penetration over an extended period of time. The present invention makes possible a variety of in-situ high pressure, high temperature MAS NMR experiments not previously achieved in the prior art.

  9. Spinning angle optical calibration apparatus

    DOE Patents [OSTI]

    Beer, Stephen K.; Pratt, II, Harold R.

    1991-01-01

    An optical calibration apparatus is provided for calibrating and reproducing spinning angles in cross-polarization, nuclear magnetic resonance spectroscopy. An illuminated magnifying apparatus enables optical setting an accurate reproducing of spinning "magic angles" in cross-polarization, nuclear magnetic resonance spectroscopy experiments. A reference mark scribed on an edge of a spinning angle test sample holder is illuminated by a light source and viewed through a magnifying scope. When the "magic angle" of a sample material used as a standard is attained by varying the angular position of the sample holder, the coordinate position of the reference mark relative to a graduation or graduations on a reticle in the magnifying scope is noted. Thereafter, the spinning "magic angle" of a test material having similar nuclear properties to the standard is attained by returning the sample holder back to the originally noted coordinate position.

  10. Mesoporous Silica Nanoparticles Loaded with Surfactant: Low Temperature Magic Angle Spinning 13C and 29Si NMR Enhanced by Dynamic Nuclear Polarization

    SciTech Connect (OSTI)

    Lafon, Olivier; Thankamony, Aany S. Lilly; Kokayashi, Takeshi; Carnevale, Diego; Vitzthum, Veronika; Slowing, Igor I.; Kandel, Kapil; Vezin, Herve; Amoureux, Jean-Paul; Bodenhausen, Geoffrey; Pruski, Marek

    2012-12-21

    We show that dynamic nuclear polarization (DNP) can be used to enhance NMR signals of 13C and 29Si nuclei located in mesoporous organic/inorganic hybrid materials, at several hundreds of nanometers from stable radicals (TOTAPOL) trapped in the surrounding frozen disordered water. The approach is demonstrated using mesoporous silica nanoparticles (MSN), functionalized with 3-(N-phenylureido)propyl (PUP) groups, filled with the surfactant cetyltrimethylammonium bromide (CTAB). The DNP-enhanced proton magnetization is transported into the mesopores via 1H1H spin diffusion and transferred to rare spins by cross-polarization, yielding signal enhancements ?on/off of around 8. When the CTAB molecules are extracted, so that the radicals can enter the mesopores, the enhancements increase to ?on/off ? 30 for both nuclei. A quantitative analysis of the signal enhancements in MSN with and without surfactant is based on a one-dimensional proton spin diffusion model. The effect of solvent deuteration is also investigated.

  11. Methods for magnetic resonance analysis using magic angle technique

    DOE Patents [OSTI]

    Hu, Jian Zhi; Wind, Robert A.; Minard, Kevin R.; Majors, Paul D.

    2011-11-22

    Methods of performing a magnetic resonance analysis of a biological object are disclosed that include placing the object in a main magnetic field (that has a static field direction) and in a radio frequency field; rotating the object at a frequency of less than about 100 Hz around an axis positioned at an angle of about 54.degree.44' relative to the main magnetic static field direction; pulsing the radio frequency to provide a sequence that includes a phase-corrected magic angle turning pulse segment; and collecting data generated by the pulsed radio frequency. In particular embodiments the method includes pulsing the radio frequency to provide at least two of a spatially selective read pulse, a spatially selective phase pulse, and a spatially selective storage pulse. Further disclosed methods provide pulse sequences that provide extended imaging capabilities, such as chemical shift imaging or multiple-voxel data acquisition.

  12. Method for high resolution magnetic resonance analysis using magic angle technique

    DOE Patents [OSTI]

    Wind, Robert A.; Hu, Jian Zhi

    2003-11-25

    A method of performing a magnetic resonance analysis of a biological object that includes placing the biological object in a main magnetic field and in a radio frequency field, the main magnetic field having a static field direction; rotating the biological object at a rotational frequency of less than about 100 Hz around an axis positioned at an angle of about 54.degree.44' relative to the main magnetic static field direction; pulsing the radio frequency to provide a sequence that includes a magic angle turning pulse segment; and collecting data generated by the pulsed radio frequency. According to another embodiment, the radio frequency is pulsed to provide a sequence capable of producing a spectrum that is substantially free of spinning sideband peaks.

  13. Moderate positive spin Hall angle in uranium

    SciTech Connect (OSTI)

    Singh, Simranjeet; Anguera, Marta; Barco, Enrique del E-mail: cwmsch@rit.edu; Springell, Ross; Miller, Casey W. E-mail: cwmsch@rit.edu

    2015-12-07

    We report measurements of spin pumping and the inverse spin Hall effect in Ni{sub 80}Fe{sub 20}/uranium bilayers designed to study the efficiency of spin-charge interconversion in a super-heavy element. We employ broad-band ferromagnetic resonance on extended films to inject a spin current from the Ni{sub 80}Fe{sub 20} (permalloy) into the uranium layer, which is then converted into an electric field by the inverse spin Hall effect. Surprisingly, our results suggest a spin mixing conductance of order 2 × 10{sup 19} m{sup −2} and a positive spin Hall angle of 0.004, which are both merely comparable with those of several transition metals. These results thus support the idea that the electronic configuration may be at least as important as the atomic number in governing spin pumping across interfaces and subsequent spin Hall effects. In fact, given that both the magnitude and the sign are unexpected based on trends in d-electron systems, materials with unfilled f-electron orbitals may hold additional exploration avenues for spin physics.

  14. Method for high resolution magnetic resonance analysis using magic angle technique

    DOE Patents [OSTI]

    Wind, Robert A.; Hu, Jian Zhi

    2004-12-28

    A method of performing a magnetic resonance analysis of a biological object that includes placing the object in a main magnetic field (that has a static field direction) and in a radio frequency field; rotating the object at a frequency of less than about 100 Hz around an axis positioned at an angle of about 54.degree.44' relative to the main magnetic static field direction; pulsing the radio frequency to provide a sequence that includes a phase-corrected magic angle turning pulse segment; and collecting data generated by the pulsed radio frequency. The object may be reoriented about the magic angle axis between three predetermined positions that are related to each other by 120.degree.. The main magnetic field may be rotated mechanically or electronically. Methods for magnetic resonance imaging of the object are also described.

  15. Method for high resolution magnetic resonance analysis using magic angle technique

    DOE Patents [OSTI]

    Wind, Robert A.; Hu, Jian Zhi

    2003-12-30

    A method of performing a magnetic resonance analysis of a biological object that includes placing the object in a main magnetic field (that has a static field direction) and in a radio frequency field; rotating the object at a frequency of less than about 100 Hz around an axis positioned at an angle of about 54.degree.44' relative to the main magnetic static field direction; pulsing the radio frequency to provide a sequence that includes a phase-corrected magic angle turning pulse segment; and collecting data generated by the pulsed radio frequency. The object may be reoriented about the magic angle axis between three predetermined positions that are related to each other by 120.degree.. The main magnetic field may be rotated mechanically or electronically. Methods for magnetic resonance imaging of the object are also described.

  16. Discrete magic angle turning system, apparatus, and process for in situ magnetic resonance spectroscopy and imaging

    DOE Patents [OSTI]

    Hu, Jian Zhi; Sears, Jr., Jesse A.; Hoyt, David W.; Wind, Robert A.

    2009-05-19

    Described are a "Discrete Magic Angle Turning" (DMAT) system, devices, and processes that combine advantages of both magic angle turning (MAT) and magic angle hopping (MAH) suitable, e.g., for in situ magnetic resonance spectroscopy and/or imaging. In an exemplary system, device, and process, samples are rotated in a clockwise direction followed by an anticlockwise direction of exactly the same amount. Rotation proceeds through an angle that is typically greater than about 240 degrees but less than or equal to about 360 degrees at constant speed for a time applicable to the evolution dimension. Back and forth rotation can be synchronized and repeated with a special radio frequency (RF) pulse sequence to produce an isotropic-anisotropic shift 2D correlation spectrum. The design permits tubes to be inserted into the sample container without introducing plumbing interferences, further allowing control over such conditions as temperature, pressure, flow conditions, and feed compositions, thus permitting true in-situ investigations to be carried out.

  17. The spin Hall angle and spin diffusion length of Pd measured by spin pumping and microwave photoresistance

    SciTech Connect (OSTI)

    Tao, X. D.; Feng, Z.; Miao, B. F.; Sun, L.; You, B.; Wu, D.; Du, J.; Zhang, W.; Ding, H. F., E-mail: hfding@nju.edu.cn [Department of Physics, National Laboratory of Solid State Microstructures, Nanjing University, 22 Hankou Road, Nanjing 210093 (China)

    2014-05-07

    We present the experimental study of the spin Hall angle (SHA) and spin diffusion length of Pd with the spin pumping and microwave photoresistance effects. The Py/Pd bilayer stripes are excited with an out-of-plane microwave magnetic field. The pure spin current is thus pumped and transforms into charge current via the inverse spin Hall effect (ISHE) in Pd layer, yielding an ISHE voltage. The ISHE voltage can be distinguished from the unwanted signal caused by the anisotropic magnetoresistance according to their different symmetries. Together with Pd thickness dependent measurements of in and out-of-plane precessing angles and effective spin mixing conductance, the SHA and spin-diffusion length of Pd are quantified as 0.0056??0.0007 and 7.3??0.7?nm, respectively.

  18. Tidal evolution of the spin-orbit angle in exoplanetary systems

    SciTech Connect (OSTI)

    Xue, Yuxin; Suto, Yasushi; Taruya, Atsushi; Hirano, Teruyuki; Fujii, Yuka; Masuda, Kento

    2014-03-20

    The angle between the stellar spin and the planetary orbit axes (the spin-orbit angle) is supposed to carry valuable information concerning the initial condition of planetary formation and subsequent migration history. Indeed, current observations of the Rossiter-McLaughlin effect have revealed a wide range of spin-orbit misalignments for transiting exoplanets. We examine in detail the tidal evolution of a simple system comprising a Sun-like star and a hot Jupiter adopting the equilibrium tide and the inertial wave dissipation effects simultaneously. We find that the combined tidal model works as a very efficient realignment mechanism; it predicts three distinct states of the spin-orbit angle (i.e., parallel, polar, and antiparallel orbits) for a while, but the latter two states eventually approach the parallel spin-orbit configuration. The intermediate spin-orbit angles as measured in recent observations are difficult to obtain. Therefore the current model cannot reproduce the observed broad distribution of the spin-orbit angles, at least in its simple form. This indicates that the observed diversity of the spin-orbit angles may emerge from more complicated interactions with outer planets and/or may be the consequence of the primordial misalignment between the protoplanetary disk and the stellar spin, which requires future detailed studies.

  19. Pf1 bacteriophage hydration by magic angle spinning solid-state NMR

    SciTech Connect (OSTI)

    Sergeyev, Ivan V.; Bahri, Salima; McDermott, Ann E.; Day, Loren A.

    2014-12-14

    High resolution two- and three-dimensional heteronuclear correlation spectroscopy ({sup 1}H–{sup 13}C, {sup 1}H–{sup 15}N, and {sup 1}H–{sup 13}C–{sup 13}C HETCOR) has provided a detailed characterization of the internal and external hydration water of the Pf1 virion. This long and slender virion (2000 nm × 7 nm) contains highly stretched DNA within a capsid of small protein subunits, each only 46 amino acid residues. HETCOR cross-peaks have been unambiguously assigned to 25 amino acids, including most external residues 1–21 as well as residues 39–40 and 43–46 deep inside the virion. In addition, the deoxyribose rings of the DNA near the virion axis are in contact with water. The sets of cross-peaks to the DNA and to all 25 amino acid residues were from the same hydration water {sup 1}H resonance; some of the assigned residues do not have exchangeable side-chain protons. A mapping of the contacts onto structural models indicates the presence of water “tunnels” through a highly hydrophobic region of the capsid. The present results significantly extend and modify results from a lower resolution study, and yield a comprehensive hydration surface map of Pf1. In addition, the internal water could be distinguished from external hydration water by means of paramagnetic relaxation enhancement. The internal water population may serve as a conveniently localized magnetization reservoir for structural studies.

  20. Strong spin-orbit coupling and Zeeman spin splitting in angle dependent magnetoresistance of Bi{sub 2}Te{sub 3}

    SciTech Connect (OSTI)

    Dey, Rik Pramanik, Tanmoy; Roy, Anupam; Rai, Amritesh; Guchhait, Samaresh; Sonde, Sushant; Movva, Hema C. P.; Register, Leonard F.; Banerjee, Sanjay K.; Colombo, Luigi

    2014-06-02

    We have studied angle dependent magnetoresistance of Bi{sub 2}Te{sub 3} thin film with field up to 9 T over 2–20 K temperatures. The perpendicular field magnetoresistance has been explained by the Hikami-Larkin-Nagaoka theory alone in a system with strong spin-orbit coupling, from which we have estimated the mean free path, the phase coherence length, and the spin-orbit relaxation time. We have obtained the out-of-plane spin-orbit relaxation time to be small and the in-plane spin-orbit relaxation time to be comparable to the momentum relaxation time. The estimation of these charge and spin transport parameters are useful for spintronics applications. For parallel field magnetoresistance, we have confirmed the presence of Zeeman effect which is otherwise suppressed in perpendicular field magnetoresistance due to strong spin-orbit coupling. The parallel field data have been explained using both the contributions from the Maekawa-Fukuyama localization theory for non-interacting electrons and Lee-Ramakrishnan theory of electron-electron interactions. The estimated Zeeman g-factor and the strength of Coulomb screening parameter agree well with the theory. Finally, the anisotropy in magnetoresistance with respect to angle has been described by the Hikami-Larkin-Nagaoka theory. This anisotropy can be used in anisotropic magnetic sensor applications.

  1. Time-domain detection of current controlled magnetization damping in Pt/Ni{sub 81}Fe{sub 19} bilayer and determination of Pt spin Hall angle

    SciTech Connect (OSTI)

    Ganguly, A.; Haldar, A.; Sinha, J.; Barman, A. E-mail: del.atkinson@durham.ac.uk; Rowan-Robinson, R. M.; Jaiswal, S.; Hindmarch, A. T.; Atkinson, D. A. E-mail: del.atkinson@durham.ac.uk

    2014-09-15

    The effect of spin torque from the spin Hall effect in Pt/Ni{sub 81}Fe{sub 19} rectangular bilayer film was investigated using time-resolved magneto-optical Kerr microscopy. Current flow through the stack resulted in a linear variation of effective damping up to ±7%, attributed to spin current injection from the Pt into the Ni{sub 81}Fe{sub 19}. The spin Hall angle of Pt was estimated as 0.11 ± 0.03. The modulation of the damping depended on the angle between the current and the bias magnetic field. These results demonstrate the importance of optical detection of precessional magnetization dynamics for studying spin transfer torque due to spin Hall effect.

  2. Quark-Gluon Plasma Model and Origin of Magic Numbers

    SciTech Connect (OSTI)

    Ghahramany, N.; Ghanaatian, M.; Hooshmand, M.

    2008-04-21

    Using Boltzman distribution in a quark-gluon plasma sample it is possible to obtain all existing magic numbers and their extensions without applying the spin and spin-orbit couplings. In this model it is assumed that in a quark-gluon thermodynamic plasma, quarks have no interactions and they are trying to form nucleons. Considering a lattice for a central quark and the surrounding quarks, using a statistical approach to find the maximum number of microstates, the origin of magic numbers is explained and a new magic number is obtained.

  3. Beam Normal Single Spin Asymmetry in Forward Angle Inelastic Electron-Proton Scattering using the Q-Weak Apparatus

    SciTech Connect (OSTI)

    ., Nuruzzaman

    2014-12-01

    The Q-weak experiment in Hall-C at the Thomas Jefferson National Accelerator Facility has made the first direct measurement of the weak charge of the proton through the precision measurement of the parity-violating asymmetry in elastic electron-proton scattering at low momentum transfer. There is also a parity conserving Beam Normal Single Spin Asymmetry or transverse asymmetry (B_n) on H_2 with a sin(phi)-like dependence due to two-photon exchange. If the size of elastic B_n is a few ppm, then a few percent residual transverse polarization in the beam, combined with small broken azimuthal symmetries in the detector, would require a few ppb correction to the Q-weak data. As part of a program of B_n background studies, we made the first measurement of B_n in the N-to-Delta(1232) transition using the Q-weak apparatus. The final transverse asymmetry, corrected for backgrounds and beam polarization, was found to be B_n = 42.82 ± 2.45 (stat) ± 16.07 (sys) ppm at beam energy E_beam = 1.155 GeV, scattering angle theta = 8.3 deg, and missing mass W = 1.2 GeV. B_n from electron-nucleon scattering is a unique tool to study the gamma^* Delta Delta form factors, and this measurement will help to improve the theoretical models on beam normal single spin asymmetry and thereby our understanding of the doubly virtual Compton scattering process. To help correct false asymmetries from beam noise, a beam modulation system was implemented to induce small position, angle, and energy changes at the target to characterize detector response to the beam jitter. Two air-core dipoles separated by ~10 m were pulsed at a time to produce position and angle changes at the target, for virtually any tune of the beamline. The beam energy was modulated using an SRF cavity. The hardware and associated control instrumentation will be described in this dissertation. Preliminary detector sensitivities were extracted which helped to reduce the width of the measured asymmetry. The beam modulation system

  4. Investigation of Mechanical Activation on Li-N-H Systems Using 6Li Magic Angle Spinning Nuclear Magnetic Resonance at Ultra-High Field

    SciTech Connect (OSTI)

    Hu, Jian Zhi; Kwak, Ja Hun; Yang, Zhenguo; Osborn, William; Markmaitree, Tippawan; Shaw, Leonard D.

    2008-07-15

    Abstract The significantly enhanced spectral resolution in the 6Li MAS NMR spectra of Li-N-H systems at ultra-high field of 21.1 tesla is exploited, for the first time, to study the detailed electronic and chemical environmental changes associated with mechanical activation of Li-N-H system using high energy balling milling. Complementary to ultra-high field studies, the hydrogen discharge dynamics are investigated using variable temperature in situ 1H MAS NMR at 7.05 tesla field. The significantly enhanced spectral resolution using ultra-high filed of 21.1 tesla was demonstrated along with several major findings related to mechanical activation, including the upfield shift of the resonances in 6Li MAS spectra induced by ball milling, more efficient mechanical activation with ball milling at liquid nitrogen temperature than with ball milling at room temperature, and greatly enhanced hydrogen discharge exhibited by the liquid nitrogen ball milled samples.

  5. Not Magic...Quantum

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

    Not Magic...Quantum 1663 Los Alamos science and technology magazine Latest Issue:July 2016 past issues All Issues » submit Not Magic...Quantum A nascent commercial quantum computer has arrived at Los Alamos and may solve certain problems with such astonishing speed that it would be like pulling answers out of a hat. July 21, 2016 commercial quantum-computer processor The world's first commercial quantum-computer processor is smaller than a wristwatch and can evaluate more possibilities

  6. Solar Magic | Open Energy Information

    Open Energy Info (EERE)

    Clara, California. SolarMagic delivers the SolarMagic Power Optimizer, which allows the solar panels in a given array to achieve maximum power regardless of whether other panels...

  7. Cross-polarization phenomena in the NMR of fast spinning solids subject to adiabatic sweeps

    SciTech Connect (OSTI)

    Wi, Sungsool E-mail: lucio.frydman@weizmann.ac.il; Gan, Zhehong; Schurko, Robert; Frydman, Lucio E-mail: lucio.frydman@weizmann.ac.il

    2015-02-14

    Cross-polarization magic-angle spinning (CPMAS) experiments employing frequency-swept pulses are explored within the context of obtaining broadband signal enhancements for rare spin S = 1/2 nuclei at very high magnetic fields. These experiments employ adiabatic inversion pulses on the S-channel ({sup 13}C) to cover a wide frequency offset range, while simultaneously applying conventional spin-locking pulse on the I-channel ({sup 1}H). Conditions are explored where the adiabatic frequency sweep width, Δν, is changed from selectively irradiating a single magic-angle-spinning (MAS) spinning centerband or sideband, to sweeping over multiple sidebands. A number of new physical features emerge upon assessing the swept-CP method under these conditions, including multiple zero- and double-quantum CP transfers happening in unison with MAS-driven rotary resonance phenomena. These were examined using an average Hamiltonian theory specifically designed to tackle these experiments, with extensive numerical simulations, and with experiments on model compounds. Ultrawide CP profiles spanning frequency ranges of nearly 6⋅γB{sub 1}{sup s} were predicted and observed utilizing this new approach. Potential extensions and applications of this extremely broadband transfer conditions are briefly discussed.

  8. Shortwave Hyperspectral Observations During MAGIC Final Campaign...

    Office of Scientific and Technical Information (OSTI)

    Title: Shortwave Hyperspectral Observations During MAGIC Final Campaign Summary The Marine ARM GPCI1 Investigation of Clouds (MAGIC) field campaign was initiated to improve our ...

  9. Shortwave Hyperspectral Observations during MAGIC

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

    ... The black contours show percent cloud absorption at 1600 nm calculated with SBDART. These ... surface-based observations of marine clouds make the MAGIC data interesting as a whole. ...

  10. A 3% Measurement of the Beam Normal Single Spin Asymmetry in Forward Angle Elastic Electron-Proton Scattering using the Qweak Setup

    SciTech Connect (OSTI)

    Waidyawansa, Dinayadura Buddhini

    2013-08-01

    The beam normal single spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable of the imaginary part of the two-photon exchange process. Moreover, it is a potential source of false asymmetry in parity violating electron scattering experiments. The Q{sub weak} experiment uses parity violating electron scattering to make a direct measurement of the weak charge of the proton. The targeted 4% measurement of the weak charge of the proton probes for parity violating new physics beyond the Standard Model. The beam normal single spin asymmetry at Q{sub weak} kinematics is at least three orders of magnitude larger than 5 ppb precision of the parity violating asymmetry. To better understand this parity conserving background, the Q{sub weak} Collaboration has performed elastic scattering measurements with fully transversely polarized electron beam on the proton and aluminum. This dissertation presents the analysis of the 3% measurement (1.3% statistical and 2.6% systematic) of beam normal single spin asymmetry in electronproton scattering at a Q2 of 0.025 (GeV/c)2. It is the most precise existing measurement of beam normal single spin asymmetry available at the time. A measurement of this precision helps to improve the theoretical models on beam normal single spin asymmetry and thereby our understanding of the doubly virtual Compton scattering process.

  11. ARM - Field Campaign - Marine ARM GPCI Investigation of Clouds (MAGIC)

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

    govCampaignsMarine ARM GPCI Investigation of Clouds (MAGIC) Campaign Links MAGIC Website ARM Data Discovery Browse Data Related Campaigns Marine ARM GPCI Investigations of Clouds (MAGIC): Measuring the Composition of Aerosol Particles 2013.07.01, Lewis, AMF Marine ARM GPCI Investigation of Clouds (MAGIC): Shortwave Hyperspectral Observations 2013.07.01, McBride, AMF Marine ARM GPCI Investigation of Clouds (MAGIC): Marine Ice Nuclei Collections 2013.06.01, DeMott, AMF Marine ARM GPCI

  12. Magic wavelengths for terahertz clock transitions

    SciTech Connect (OSTI)

    Zhou Xiaoji; Xu Xia; Chen Xuzong; Chen Jingbiao

    2010-01-15

    Magic wavelengths for laser trapping of boson isotopes of alkaline-earth metal atoms Sr, Ca, and Mg are investigated while considering terahertz clock transitions between the {sup 3}P{sub 0}, {sup 3}P{sub 1}, and {sup 3}P{sub 2} metastable triplet states. Our calculation shows that magic wavelengths for laser trapping do exist. This result is important because those metastable states have already been used to make accurate clocks in the terahertz frequency domain. Detailed discussions for magic wavelengths for terahertz clock transitions are given in this article.

  13. Recent Results from the MAGIC Telescope

    SciTech Connect (OSTI)

    Bock, Rudolf K.

    2005-02-21

    Some recent results are shown, obtained during the commissioning period of the MAGIC telescope. They demonstrate that the telescope is now approaching a performance level suitable for physics observations.

  14. Magic Wind LLC | Open Energy Information

    Open Energy Info (EERE)

    Wind LLC Jump to: navigation, search Name: Magic Wind, LLC Place: Buhl, Idaho Zip: 83316 Sector: Wind energy Product: A small Idaho-based limited liability company developing the...

  15. Status and recent results of MAGIC

    SciTech Connect (OSTI)

    Rico, Javier; Wagner, Robert

    2009-04-08

    MAGIC is a single-dish Cherenkov telescope located on La Palma (Spain), hence with an optimal view on the Northern sky. Sensitive in the 30 GeV-30 TeV energy band, it is nowadays the only ground-based instrument being able to measure high-energy {gamma}-rays below 100 GeV. We review the most recent experimental results obtained using MAGIC.

  16. Lab scientists track Santa's magical journey

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

    Santa's magical journey Lab scientists track Santa's magical journey Los Alamos trackers will use state-of-the-art technology to mark the course taken by Old St. Nick and his reindeer. December 20, 2010 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National Laboratory

  17. ARM - Field Campaign - Marine ARM GPCI Investigations of Clouds (MAGIC):

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

    Parsivel Disdrometer support for MAGIC govCampaignsMarine ARM GPCI Investigations of Clouds (MAGIC): Parsivel Disdrometer support for MAGIC Campaign Links Field Campaign Report ARM Data Discovery Browse Data Related Campaigns Marine ARM GPCI Investigation of Clouds (MAGIC) 2012.10.01, Lewis, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Marine ARM GPCI Investigations of Clouds (MAGIC): Parsivel Disdrometer support for MAGIC

  18. Solid-State Selective 13C Excitation and Spin Diffusion NMR to Resolve Spatial Dimensions in Plant Cell Walls

    SciTech Connect (OSTI)

    Foston, M.; Katahira, R.; Gjersing, E.; Davis, M. F.; Ragauskas, A. J.

    2012-02-15

    The average spatial dimensions between major biopolymers within the plant cell wall can be resolved using a solid-state NMR technique referred to as a {sup 13}C cross-polarization (CP) SELDOM (selectively by destruction of magnetization) with a mixing time delay for spin diffusion. Selective excitation of specific aromatic lignin carbons indicates that lignin is in close proximity to hemicellulose followed by amorphous and finally crystalline cellulose. {sup 13}C spin diffusion time constants (T{sub SD}) were extracted using a two-site spin diffusion theory developed for {sup 13}C nuclei under magic angle spinning (MAS) conditions. These time constants were then used to calculate an average lower-limit spin diffusion length between chemical groups within the plant cell wall. The results on untreated {sup 13}C enriched corn stover stem reveal that the lignin carbons are, on average, located at distances {approx}0.7-2.0 nm from the carbons in hemicellulose and cellulose, whereas the pretreated material had larger separations.

  19. Jefferson Lab announces two Fall Science Series events -- featuring magic

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

    and football | Jefferson Lab events -- featuring magic and football Jefferson Lab announces two Fall Science Series events - featuring magic and football October 4, 2005 Using humor, stagecraft and lighting, along with laboratory experiments disguised as magical illusion, the audience will view science from a perspective most have never seen before with Bob Friedhoffer, author, scientist and magician. He will conduct "Einstein and Beyond - The Magic Show" on Tuesday, Oct. 25 at the

  20. Marine Ice Nuclei Collections … MAGIC (MAGIC-IN) Final Campaign...

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

    ... low Chlorophyll-a (with the exception of near-shore) ocean regions, which exist along the MAGIC transect. Current analyses suggest that INP numbers in the marine boundary ...

  1. Magic Valley Electric Coop Inc | Open Energy Information

    Open Energy Info (EERE)

    Twitter: @magicvalleyEC Facebook: https:www.facebook.comMagicValleyEC?refts Outage Hotline: 1-866-225-5683 Outage Map: www.magicvalley.coopmapoutag...

  2. MAGIC Cloud Properties from Zenith Radiance Data Final Campaign...

    Office of Scientific and Technical Information (OSTI)

    Title: MAGIC Cloud Properties from Zenith Radiance Data Final Campaign Summary Cloud droplet size and optical depth are the most fundamental properties for understanding cloud ...

  3. SNLSimMagic v 2.0

    SciTech Connect (OSTI)

    2015-10-21

    This software is an iOS (Apple) Augmented Reality (AR) application that runs on the iPhone and iPad. It is designed to scan in a photograph or graphic and “play” an associated video. This release, SNLSimMagic, was built using Wikitude Augmented Reality (AR) software development kit (SDK) integrated into Apple iOS SDK application and the Cordova libraries. These codes enable the generation of runtime targets using cloud recognition and developer-defined target features which are then accessed by means of a custom application.

  4. SNLSimMagic v 2.0

    Energy Science and Technology Software Center (OSTI)

    2015-10-21

    This software is an iOS (Apple) Augmented Reality (AR) application that runs on the iPhone and iPad. It is designed to scan in a photograph or graphic and “play” an associated video. This release, SNLSimMagic, was built using Wikitude Augmented Reality (AR) software development kit (SDK) integrated into Apple iOS SDK application and the Cordova libraries. These codes enable the generation of runtime targets using cloud recognition and developer-defined target features which are then accessedmore » by means of a custom application.« less

  5. MAGIC: Marine ARM GPCI Investigation of Clouds

    SciTech Connect (OSTI)

    Lewis, ER; Wiscombe, WJ; Albrecht, BA; Bland, GL; Flagg, CN; Klein, SA; Kollias, P; Mace, G; Reynolds, RM; Schwartz, SE; Siebesma, AP; Teixeira, J; Wood, R; Zhang, M

    2012-10-03

    The second Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF2) will be deployed aboard the Horizon Lines cargo container ship merchant vessel (M/V) Spirit for MAGIC, the Marine ARM GPCI1 Investigation of Clouds. The Spirit will traverse the route between Los Angeles, California, and Honolulu, Hawaii, from October 2012 through September 2013 (except for a few months in the middle of this time period when the ship will be in dry dock). During this field campaign, AMF2 will observe and characterize the properties of clouds and precipitation, aerosols, and atmospheric radiation; standard meteorological and oceanographic variables; and atmospheric structure. There will also be two intensive observational periods (IOPs), one in January 2013 and one in July 2013, during which more detailed measurements of the atmospheric structure will be made.

  6. Manipulating topological states by imprinting non-collinear spin...

    Office of Scientific and Technical Information (OSTI)

    We observe distinct spin textures, e.g. vortices, magnetic swirls with tunable opening angle, donut states and skyrmion core configurations. We show that applying a small magnetic ...

  7. The Chemistry Magic Show Captivates Kids | GE Global Research

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

    Chemistry Magic Show Captivates Kids Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new window) Click to ...

  8. ARM - Field Campaign - Marine ARM GPCI Investigations of Clouds (MAGIC):

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

    Infrared Seasurface Temperature Autonomous Radiometer (ISAR) Infrared Seasurface Temperature Autonomous Radiometer (ISAR) ARM Data Discovery Browse Data Related Campaigns Marine ARM GPCI Investigation of Clouds (MAGIC) 2012.10.01, Lewis, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Marine ARM GPCI Investigations of Clouds (MAGIC): Infrared Seasurface Temperature Autonomous Radiometer (ISAR) 2012.09.01 - 2013.09.30 Lead

  9. Intriguing structures and magic sizes of heavy noble metal nanoclusters around size 55 governed by relativistic effect and covalent bonding

    SciTech Connect (OSTI)

    Zhao, X. J.; Xue, X. L.; Jia, Yu; Guo, Z. X.; Li, S. F.; Zhang, Zhenyu; Gao, Y. F.

    2015-11-07

    Nanoclusters usually display exotic physical and chemical properties due to their intriguing geometric structures in contrast to their bulk counterparts. By means of first-principles calculations within density functional theory, we find that heavy noble metal Pt{sub N} nanoclusters around the size N = 55 begin to prefer an open configuration, rather than previously reported close-packed icosahedron or core-shell structures. Particularly, for Pt{sub N}, the widely supposed icosahedronal magic cluster is changed to a three-atomic-layered structure with D{sub 6h} symmetry, which can be well addressed by our recently established generalized Wulff construction principle (GWCP). However, the magic number of Pt{sub N} clusters around 55 is shifted to a new odd number of 57. The high symmetric three-layered Pt{sub 57} motif is mainly stabilized by the enhanced covalent bonding contributed by both spin-orbital coupling effect and the open d orbital (5d{sup 9}6s{sup 1}) of Pt, which result in a delicate balance between the enhanced Pt–Pt covalent bonding of the interlayers and negligible d dangling bonds on the cluster edges. These findings about Pt{sub N} clusters are also applicable to Ir{sub N} clusters, but qualitatively different from their earlier neighboring element Os and their later neighboring element Au. The magic numbers for Os and Au are even, being 56 and 58, respectively. The findings of the new odd magic number 57 are the important supplementary of the recently established GWCP.

  10. Spin-torque switching of a nano-magnet using giant spin hall effect

    SciTech Connect (OSTI)

    Penumatcha, Ashish V. Das, Suprem R.; Chen, Zhihong; Appenzeller, Joerg

    2015-10-15

    The Giant Spin Hall Effect(GSHE) in metals with high spin-orbit coupling is an efficient way to convert charge currents to spin currents, making it well-suited for writing information into magnets in non-volatile magnetic memory as well as spin-logic devices. We demonstrate the switching of an in-plane CoFeB magnet using a combination of GSHE and an external magnetic field. The magnetic field dependence of the critical current is used to estimate the spin hall angle with the help of a thermal activation model for spin-transfer torque switching of a nanomagnet.

  11. Magic ratio of window width to grating period for van der Waals potential measurements using material gratings

    SciTech Connect (OSTI)

    Lonij, Vincent P. A.; Holmgren, William F.; Cronin, Alexander D.

    2009-12-15

    We report improved precision measurements of the van der Waals potential strength (C{sub 3}) for Na atoms and a silicon-nitride (SiN{sub x}) surface. We studied diffraction from nanofabricated gratings with a particular 'magic' open fraction that allows us to determine C{sub 3} without the need for separate measurements of the width of the grating openings. Therefore, finding the magic open fraction improves the precision of C{sub 3} measurements. The same effect is demonstrated for a grating with an arbitrary open fraction by rotating it to a particular 'magic' angle, yielding C{sub 3}=3.42+-0.19 eV A{sup 3} for Na and a SiN{sub x} surface. This precision is sufficient to detect a change in C{sub 3} due to a thin metal coating on the grating surface. We discuss the contribution to C{sub 3} of core electrons and edge effects.

  12. Y{sub 3}Fe{sub 5}O{sub 12} spin pumping for quantitative understanding of pure spin transport and spin Hall effect in a broad range of materials (invited)

    SciTech Connect (OSTI)

    Du, Chunhui; Wang, Hailong; Hammel, P. Chris; Yang, Fengyuan

    2015-05-07

    Using Y{sub 3}Fe{sub 5}O{sub 12} (YIG) thin films grown by our sputtering technique, we study dynamic spin transport in nonmagnetic, ferromagnetic, and antiferromagnetic (AF) materials by ferromagnetic resonance spin pumping. From both inverse spin Hall effect and damping enhancement, we determine the spin mixing conductance and spin Hall angle in many metals. Surprisingly, we observe robust spin conduction in AF insulators excited by an adjacent YIG at resonance. This demonstrates that YIG spin pumping is a powerful and versatile tool for understanding spin Hall physics, spin-orbit coupling, and magnetization dynamics in a broad range of materials.

  13. ARM - Field Campaign - Marine ARM GPCI Investigations of Clouds (MAGIC):

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

    Cloud Properties from Zenith Radiance Data Cloud Properties from Zenith Radiance Data Campaign Links Final Campaign Summary ARM Data Discovery Browse Data Related Campaigns Marine ARM GPCI Investigation of Clouds (MAGIC) 2012.10.01, Lewis, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Marine ARM GPCI Investigations of Clouds (MAGIC): Cloud Properties from Zenith Radiance Data 2012.10.01 - 2013.09.30 Lead Scientist : J.-Y.

  14. Daniela Rodica Radu

    Office of Scientific and Technical Information (OSTI)

    ... The United States Government has assigned the DOE Report number ... Magic-angle sample spinning rate was maintained at 10 ... their nuclei, triggering an apoptotic death mechanism. ...

  15. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Patent Program Document Software Manual Technical Report ThesisDissertation ... H. F. ; Lercher, Johannes A. Magic angle spinning (MAS) nuclear magnetic resonance (NMR) ...

  16. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Patent Program Document Software Manual Technical Report ThesisDissertation ... with the very high magic angle sample spinning rates needed for operation at the high ...

  17. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... (1) materials science (1) nmr spectra (1) nuclear magnetic resonance (1) ... (XRD) and sup 29Si magic-angle spinning (MAS) nuclear magnetic resonance (NMR). ...

  18. Spin transport and spin polarization properties in double-stranded DNA

    SciTech Connect (OSTI)

    Simchi, Hamidreza; Esmaeilzadeh, Mahdi Mazidabadi, Hossein

    2013-11-21

    We study the spin-dependent electron transport through a double-stranded DNA (dsDNA) using the Bogoliubov-de Gennes equations and non-equilibrium Green's function method. We calculate the spin-dependent electron conductance and spin-polarization for different lengths, helix angles, twist angles of dsDNA, the environment-induced dephasing factors, and hopping integral. It is shown that the conductance decreases by increasing the length and dephasing factor. Also, we show that the spin-polarization depends on the helical symmetry and the length of DNA. It is shown that the double-stranded DNA can act as a perfect spin filter. Finally, we show that the sign of spin polarization can be inverted from +1 (−1) to −1 (+1) for some values of hopping integral.

  19. Exploring a possible origin of a 14 deg y-normal spin tilt at RHIC polarimeter

    SciTech Connect (OSTI)

    Meot, F.; Huang, H.

    2015-06-15

    A possible origin of a 14 deg y-normal spin n0 tilt at the polarimeter is in snake angle defects. This possible cause is investigated by scanning the snake axis angle µ, and the spin rotation angle at the snake, φ, in the vicinity of their nominal values.

  20. ANGLE Plc | Open Energy Information

    Open Energy Info (EERE)

    ANGLE Plc Jump to: navigation, search Name: ANGLE Plc Place: United Kingdom Sector: Services Product: General Financial & Legal Services ( Quoted company ) References: ANGLE Plc1...

  1. Emergent spin

    SciTech Connect (OSTI)

    Creutz, Michael

    2014-03-15

    Quantum mechanics and relativity in the continuum imply the well known spinstatistics connection. However for particles hopping on a lattice, there is no such constraint. If a lattice model yields a relativistic field theory in a continuum limit, this constraint must emerge for physical excitations. We discuss a few models where a spin-less fermion hopping on a lattice gives excitations which satisfy the continuum Dirac equation. This includes such well known systems such as graphene and staggered fermions. -- Highlights: The spinstatistics theorem is not required for particles on a lattice. Spin emerges dynamically when spinless fermions have a relativistic continuum limit. Graphene and staggered fermions are examples of this phenomenon. The phenomenon is intimately tied to chiral symmetry and fermion doubling. Anomaly cancellation is a crucial feature of any valid lattice fermion action.

  2. Nuclear spin circular dichroism

    SciTech Connect (OSTI)

    Vaara, Juha; Rizzo, Antonio; Kauczor, Joanna; Norman, Patrick; Coriani, Sonia

    2014-04-07

    Recent years have witnessed a growing interest in magneto-optic spectroscopy techniques that use nuclear magnetization as the source of the magnetic field. Here we present a formulation of magnetic circular dichroism (CD) due to magnetically polarized nuclei, nuclear spin-induced CD (NSCD), in molecules. The NSCD ellipticity and nuclear spin-induced optical rotation (NSOR) angle correspond to the real and imaginary parts, respectively, of (complex) quadratic response functions involving the dynamic second-order interaction of the electron system with the linearly polarized light beam, as well as the static magnetic hyperfine interaction. Using the complex polarization propagator framework, NSCD and NSOR signals are obtained at frequencies in the vicinity of optical excitations. Hartree-Fock and density-functional theory calculations on relatively small model systems, ethene, benzene, and 1,4-benzoquinone, demonstrate the feasibility of the method for obtaining relatively strong nuclear spin-induced ellipticity and optical rotation signals. Comparison of the proton and carbon-13 signals of ethanol reveals that these resonant phenomena facilitate chemical resolution between non-equivalent nuclei in magneto-optic spectra.

  3. Maria Goeppert Mayer, the Nuclear Shell Structure, and Magic Numbers

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

    Maria Goeppert-Mayer, the Nuclear Shell Model, and Magic Numbers Resources with Additional Information Maria Goeppert-Mayer Courtesy Argonne National Laboratory While working at Argonne National Laboratory (ANL) in 1948, physicist Maria Goeppert-Mayer developed the explanation of how neutrons and protons within atomic nuclei are structured. Called the "nuclear shell model," her work explains why the nuclei of some atoms are more stable than others and why some elements have many

  4. A New Spin on Photoemission Spectroscopy

    SciTech Connect (OSTI)

    Advanced Light Source; Jozwiak, Chris

    2008-12-18

    The electronic spin degree of freedom is of general fundamental importance to all matter. Understanding its complex roles and behavior in the solid state, particularly in highly correlated and magnetic materials, has grown increasingly desirable as technology demands advanced devices and materials based on ever stricter comprehension and control of the electron spin. However, direct and efficient spin dependent probes of electronic structure are currently lacking. Angle Resolved Photoemission Spectroscopy (ARPES) has become one of the most successful experimental tools for elucidating solid state electronic structures, bolstered bycontinual breakthroughs in efficient instrumentation. In contrast, spin-resolved photoemission spectroscopy has lagged behind due to a lack of similar instrumental advances. The power of photoemission spectroscopy and the pertinence of electronic spin in the current research climate combine to make breakthroughs in Spin and Angle Resolved Photoemission Spectroscopy (SARPES) a high priority . This thesis details the development of a unique instrument for efficient SARPES and represents a radical departure from conventional methods. A custom designed spin polarimeter based on low energy exchange scattering is developed, with projected efficiency gains of two orders of magnitude over current state-of-the-art polarimeters. For energy analysis, the popular hemispherical analyzer is eschewed for a custom Time-of-Flight (TOF) analyzer offering an additional order of magnitude gain in efficiency. The combined instrument signifies the breakthrough needed to perform the high resolution SARPES experiments necessary for untangling the complex spin-dependent electronic structures central to today?s condensed matter physics.

  5. Spin ejector

    DOE Patents [OSTI]

    Andersen, John A. (Alburquerque, NM); Flanigan, John J. (Alburquerque, NM); Kindley, Robert J. (Alburquerque, NM)

    1978-01-01

    The disclosure relates to an apparatus for spin ejecting a body having a flat plate base containing bosses. The apparatus has a base plate and a main ejection shaft extending perpendicularly from the base plate. A compressible cylindrical spring is disposed about the shaft. Bearings are located between the shaft and the spring. A housing containing a helical aperture releasably engages the base plate and surrounds the shaft bearings and the spring. A piston having an aperture follower disposed in the housing aperture is seated on the spring and is guided by the shaft and the aperture. The spring is compressed and when released causes the piston to spin eject the body.

  6. Theory of magic optical traps for Zeeman-insensitive clock transitions in alkali-metal atoms

    SciTech Connect (OSTI)

    Derevianko, Andrei

    2010-05-15

    Precision measurements and quantum-information processing with cold atoms may benefit from trapping atoms with specially engineered, 'magic' optical fields. At the magic trapping conditions, the relevant atomic properties remain immune to strong perturbations by the trapping fields. Here we develop a theoretical analysis of magic trapping for especially valuable Zeeman-insensitive clock transitions in alkali-metal atoms. The involved mechanism relies on applying a magic bias B field along a circularly polarized trapping laser field. We map out these B fields as a function of trapping laser wavelength for all commonly used alkalis. We also highlight a common error in evaluating Stark shifts of hyperfine manifolds.

  7. NMR system and method having a permanent magnet providing a rotating magnetic field

    DOE Patents [OSTI]

    Schlueter, Ross D [Berkeley, CA; Budinger, Thomas F [Berkeley, CA

    2009-05-19

    Disclosed herein are systems and methods for generating a rotating magnetic field. The rotating magnetic field can be used to obtain rotating-field NMR spectra, such as magic angle spinning spectra, without having to physically rotate the sample. This result allows magic angle spinning NMR to be conducted on biological samples such as live animals, including humans.

  8. Characterization of a novel two dimensional diode array the ''magic plate'' as a radiation detector for radiation therapy treatment

    SciTech Connect (OSTI)

    Wong, J. H. D.; Fuduli, I.; Carolan, M.; Petasecca, M.; Lerch, M. L. F.; Perevertaylo, V. L.; Metcalfe, P.; Rosenfeld, A. B.

    2012-05-15

    Purpose: Intensity modulated radiation therapy (IMRT) utilizes the technology of multileaf collimators to deliver highly modulated and complex radiation treatment. Dosimetric verification of the IMRT treatment requires the verification of the delivered dose distribution. Two dimensional ion chamber or diode arrays are gaining popularity as a dosimeter of choice due to their real time feedback compared to film dosimetry. This paper describes the characterization of a novel 2D diode array, which has been named the ''magic plate'' (MP). It was designed to function as a 2D transmission detector as well as a planar detector for dose distribution measurements in a solid water phantom for the dosimetric verification of IMRT treatment delivery. Methods: The prototype MP is an 11 x 11 detector array based on thin (50 {mu}m) epitaxial diode technology mounted on a 0.6 mm thick Kapton substrate using a proprietary ''drop-in'' technology developed by the Centre for Medical Radiation Physics, University of Wollongong. A full characterization of the detector was performed, including radiation damage study, dose per pulse effect, percent depth dose comparison with CC13 ion chamber and build up characteristics with a parallel plane ion chamber measurements, dose linearity, energy response and angular response. Results: Postirradiated magic plate diodes showed a reproducibility of 2.1%. The MP dose per pulse response decreased at higher dose rates while at lower dose rates the MP appears to be dose rate independent. The depth dose measurement of the MP agrees with ion chamber depth dose measurements to within 0.7% while dose linearity was excellent. MP showed angular response dependency due to the anisotropy of the silicon diode with the maximum variation in angular response of 10.8% at gantry angle 180 deg. Angular dependence was within 3.5% for the gantry angles {+-} 75 deg. The field size dependence of the MP at isocenter agrees with ion chamber measurement to within 1.1%. In

  9. Spin current and inverse spin Hall effect in ferromagnetic metals probed by Y{sub 3}Fe{sub 5}O{sub 12}-based spin pumping

    SciTech Connect (OSTI)

    Wang, Hailong; Du, Chunhui; Chris Hammel, P. Yang, Fengyuan

    2014-05-19

    Using ferromagnetic (FM) resonance spin pumping, we observe injection of spin currents from Y{sub 3}Fe{sub 5}O{sub 12} (YIG) films to FM metals, including Ni{sub 81}Fe{sub 19} (Py), Fe, Co, and Ni, and detection of spin currents by inverse spin Hall effect (ISHE) in the FM metals. We obtain a high effective spin mixing conductance of 6.3 × 10{sup 18} m{sup −2} in a YIG/Cu/Py trilayer and a spin Hall angle of 0.020 for Py. The spin pumping signals in Fe, Co, and Ni confirm the mechanism of ISHE in FMs is the inverse process of the anomalous Hall effect.

  10. Experimental evidences of a large extrinsic spin Hall effect in AuW alloy

    SciTech Connect (OSTI)

    Laczkowski, P.; Rojas-Sánchez, J.-C.

    2014-04-07

    We report an experimental study of a gold-tungsten alloy (7 at. % W concentration in Au host) displaying remarkable properties for spintronics applications using both magneto-transport in lateral spin valve devices and spin-pumping with inverse spin Hall effect experiments. A very large spin Hall angle of about 10% is consistently found using both techniques with the reliable spin diffusion length of 2 nm estimated by the spin sink experiments in the lateral spin valves. With its chemical stability, high resistivity, and small induced damping, this AuW alloy may find applications in the nearest future.

  11. Observation of spin-charge conversion in chemical-vapor-deposition-grown single-layer graphene

    SciTech Connect (OSTI)

    Ohshima, Ryo; Sakai, Atsushi; Ando, Yuichiro; Shiraishi, Masashi; Shinjo, Teruya; Kawahara, Kenji; Ago, Hiroki

    2014-10-20

    Conversion of pure spin current to charge current in single-layer graphene (SLG) is investigated by using spin pumping. Large-area SLG grown by chemical vapor deposition is used for the conversion. Efficient spin accumulation in SLG by spin pumping enables observing an electromotive force produced by the inverse spin Hall effect (ISHE) of SLG. The spin Hall angle of SLG is estimated to be 6.1 × 10{sup −7}. The observed ISHE in SLG is ascribed to its non-negligible spin-orbit interaction in SLG.

  12. Reducing galvanomagnetic effects in spin pumping measurement with Co{sub 75}Fe{sub 25} as a spin injector

    SciTech Connect (OSTI)

    Haidar, S. M. Iguchi, R.; Yagmur, A.; Lustikova, J.; Shiomi, Y.; Saitoh, E.

    2015-05-14

    We have investigated dc voltage generation induced by ferromagnetic resonance in a Co{sub 75}Fe{sub 25}/Pt film. In order to reduce rectification effects of anisotropic magnetoresistance and the planar Hall effect, which may be observed simultaneously with the inverse spin Hall effect, we selected Co{sub 75}Fe{sub 25} with extremely small anisotropic magnetoresistance as a spin injector. Using the difference in the spectral shape of voltage and in the angle dependence of in-plane magnetization among the effects, we demonstrated that the generated dc voltage is governed by the inverse spin Hall effect induced by spin pumping.

  13. RHIC spin physics: Proceedings. Volume 7

    SciTech Connect (OSTI)

    1998-12-01

    This proceedings compiles one-page summaries and five transparencies for each talk, with the intention that the speaker should include a web location for additional information in the summary. Also, email addresses are given with the participant list. The order follows the agenda: gluon, polarimetry, accelerator, W production and quark/antiquark polarization, parity violation searches, transversity, single transverse spin, small angle elastic scattering, and the final talk on ep collisions at RHIC. The authors begin the Proceedings with the full set of transparencies from Bob Jaffe`s colloquium on spin, by popular request.

  14. Conversion of pure spin current to charge current in amorphous bismuth

    SciTech Connect (OSTI)

    Emoto, H.; Ando, Y.; Shinjo, T.; Shiraishi, M.; Shikoh, E.; Fuseya, Y.

    2014-05-07

    Spin Hall angle and spin diffusion length in amorphous bismuth (Bi) are investigated by using conversion of a pure spin current to a charge current in a spin pumping technique. In Bi/Ni{sub 80}Fe{sub 20}/Si(100) sample, a clear direct current (DC) electromotive force due to the inverse spin Hall effect of the Bi layer is observed at room temperature under a ferromagnetic resonance condition of the Ni{sub 80}Fe{sub 20} layer. From the Bi thickness dependence of the DC electromotive force, the spin Hall angle and the spin diffusion length of the amorphous Bi film are estimated to be 0.02 and 8?nm, respectively.

  15. Spin-Torque

    Office of Scientific and Technical Information (OSTI)

    Spin-Torque in Systems with Inhomogeneous Magnetization Grant No. DE-FG02-04ER46170 Final ... I. OVERVIEW The work performed under this grant focused on the phenomenon of spin-transfer ...

  16. Direct observation of a resolvable spin separation in the spin Hall effect of light at an air-glass interface

    SciTech Connect (OSTI)

    Ren, Jin-Li; Wang, Bo; Xiao, Yun-Feng; Gong, Qihuang; Li, Yan

    2015-09-14

    We theoretically and experimentally demonstrate that it is possible to directly observe the resolvable spin separation in the spin Hall effect of light at an air-glass interface by choosing optimal parameters. When a P-polarized light with a beam waist of 10 μm is incident around Brewster's angle, the two spin components of the reflected beam can be completely separated by eliminating the influence of the in-plane wavevector spread. This not only obviously reveals the strong impacts of the polarization state, the incident angle, the beam waist, and the in-plane wavevector spread, but also intuitively visualizes the observation of the spin Hall effect of light.

  17. A spin-orbit alignment for the hot Jupiter HATS-3b

    SciTech Connect (OSTI)

    Addison, B. C.; Tinney, C. G.; Wright, D. J.; Bayliss, D.

    2014-09-10

    We have measured the alignment between the orbit of HATS-3b (a recently discovered, slightly inflated Hot Jupiter) and the spin axis of its host star. Data were obtained using the CYCLOPS2 optical-fiber bundle and its simultaneous calibration system feeding the UCLES spectrograph on the Anglo-Australian Telescope. The sky-projected spin-orbit angle of ? = 3 25 was determined from spectroscopic measurements of the Rossiter-McLaughlin effect. This is the first exoplanet discovered through the HATSouth transit survey to have its spin-orbit angle measured. Our results indicate that the orbital plane of HATS-3b is consistent with being aligned to the spin axis of its host star. The low obliquity of the HATS-3 system, which has a relatively hot mid F-type host star, agrees with the general trend observed for Hot Jupiter host stars with effective temperatures >6250 K to have randomly distributed spin-orbit angles.

  18. Ring magnet firing angle control

    DOE Patents [OSTI]

    Knott, M.J.; Lewis, L.G.; Rabe, H.H.

    1975-10-21

    A device is provided for controlling the firing angles of thyratrons (rectifiers) in a ring magnet power supply. A phase lock loop develops a smooth ac signal of frequency equal to and in phase with the frequency of the voltage wave developed by the main generator of the power supply. A counter that counts from zero to a particular number each cycle of the main generator voltage wave is synchronized with the smooth AC signal of the phase lock loop. Gates compare the number in the counter with predetermined desired firing angles for each thyratron and with coincidence the proper thyratron is fired at the predetermined firing angle.

  19. Influence of the Torsion Angle ...

    Office of Scientific and Technical Information (OSTI)

    ... rings, usually reported as the N C C N angle, obtained from solid-state crystal structures. ... Synthesis and Physical Properties. The preparation o f C p*2Y b(3,3'-M b ip y ) ...

  20. Geek-Up[09.24.10] -- Magical BEANs, Combating Bacteria's Resistance to

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

    Antibiotics and the ChemCam's Journey to Mars | Department of Energy 9.24.10] -- Magical BEANs, Combating Bacteria's Resistance to Antibiotics and the ChemCam's Journey to Mars Geek-Up[09.24.10] -- Magical BEANs, Combating Bacteria's Resistance to Antibiotics and the ChemCam's Journey to Mars September 24, 2010 - 5:19pm Addthis Check out the ChemCam close-up, which will reveal which elements are present in Mars' rocks and soils. Elizabeth Meckes Elizabeth Meckes Director of User Experience

  1. Aqueous Synthesis of Zinc Blende CdTe/CdS Magic-Core/Thick-Shell

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

    Tetrahedral Shaped Nanocrystals with Emission Tunable to Near-Infrared Aqueous Synthesis of Zinc Blende CdTe/CdS Magic-Core/Thick-Shell Tetrahedral Shaped Nanocrystals with Emission Tunable to Near-Infrared Authors: Deng, Z., Schulz, O., Lin, S., Ding, B., Liu, X., Wei, X., Ros, R., Liu, Y., Yan, H., and Francis, M. Title: Aqueous Synthesis of Zinc Blende CdTe/CdS Magic-Core/Thick-Shell Tetrahedral Shaped Nanocrystals with Emission Tunable to Near-Infrared Source: Journal of the American

  2. End-compensated magnetostatic cavity for polarized {sup 3}He neutron spin filters

    SciTech Connect (OSTI)

    McIver, J. W.; Erwin, R.; Gentile, T. R.; Chen, W. C.

    2009-06-15

    We have expanded upon the ''Magic Box'' concept, a coil driven magnetic parallel plate capacitor constructed out of mu-metal, by introducing compensation sections at the ends of the box that are tuned to limit end-effects similar to those of short solenoids. This ability has reduced the length of the magic box design without sacrificing any loss in field homogeneity, making the device far more applicable to the often space limited neutron beam line. The appeal of the design beyond affording longer polarized {sup 3}He lifetimes is that it provides a vertical guide field, which facilitates neutron spin transport for typical polarized beam experiments. We have constructed two end-compensated magic boxes of dimensions 28.4x40x15 cm{sup 3} (lengthxwidthxheight) with measured, normalized volume-averaged transverse field gradients ranging from 3.3x10{sup -4} to 6.3x10{sup -4} cm{sup -1} for cell sizes ranging from 8.1x6.0 to 12.0x7.9 cm{sup 2} (diameterxlength), respectively.

  3. Spin caloritronics in graphene

    SciTech Connect (OSTI)

    Ghosh, Angsula; Frota, H. O.

    2015-06-14

    Spin caloritronics, the combination of spintronics with thermoelectrics, exploiting both the intrinsic spin of the electron and its associated magnetic moment in addition to its fundamental electronic charge and temperature, is an emerging technology mainly in the development of low-power-consumption technology. In this work, we study the thermoelectric properties of a Rashba dot attached to two single layer/bilayer graphene sheets as leads. The temperature difference on the two graphene leads induces a spin current, which depends on the temperature and chemical potential. We demonstrate that the Rashba dot behaves as a spin filter for selected values of the chemical potential and is able to filter electrons by their spin orientation. The spin thermopower has also been studied where the effects of the chemical potential, temperature, and also the Rashba term have been observed.

  4. Spin coating apparatus

    DOE Patents [OSTI]

    Torczynski, John R.

    2000-01-01

    A spin coating apparatus requires less cleanroom air flow than prior spin coating apparatus to minimize cleanroom contamination. A shaped exhaust duct from the spin coater maintains process quality while requiring reduced cleanroom air flow. The exhaust duct can decrease in cross section as it extends from the wafer, minimizing eddy formation. The exhaust duct can conform to entrainment streamlines to minimize eddy formation and reduce interprocess contamination at minimal cleanroom air flow rates.

  5. Optical detection of spin Hall effect in metals

    SciTech Connect (OSTI)

    Erve, O. M. J. van ‘t Hanbicki, A. T.; McCreary, K. M.; Li, C. H.; Jonker, B. T.

    2014-04-28

    Optical techniques have been widely used to probe the spin Hall effect in semiconductors. In metals, however, only electrical methods such as nonlocal spin valve transport, ferromagnetic resonance, or spin torque transfer experiments have been successful. These methods require complex processing techniques and measuring setups. We show here that the spin Hall effect can be observed in non-magnetic metals such as Pt and β-W, using a standard bench top magneto-optical Kerr system with very little sample preparation. Applying a square wave current and using Fourier analysis significantly improve our detection level. One can readily determine the angular dependence of the induced polarization on the bias current direction (very difficult to do with voltage detection), the orientation of the spin Hall induced polarization, and the sign of the spin Hall angle. This optical approach is free from the complications of various resistive effects, which can compromise voltage measurements. This opens up the study of spin Hall effect in metals to a variety of spin dynamic and spatial imaging experiments.

  6. Anomalous spin precession and spin Hall effect in semiconductor...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Anomalous spin precession and spin Hall effect in semiconductor quantum wells Citation Details In-Document Search Title: Anomalous ...

  7. Micromagnetic study of spin transfer switching with a spin polarization tilted out of the free layer plane

    SciTech Connect (OSTI)

    Chaves-O'Flynn, Gabriel D. Wolf, Georg; Pinna, Daniele; Kent, Andrew D.

    2015-05-07

    We present the results of zero temperature macrospin and micromagnetic simulations of spin transfer switching of thin film nanomagnets in the shape of an ellipse with a spin-polarization tilted out of the layer plane. The perpendicular component of the spin-polarization is shown to increase the reversal speed, leading to a lower current for switching in a given time. However, for tilt angles larger than a critical angle, the layer magnetization starts to precess about an out-of-plane axis, which leads to a final magnetization state that is very sensitive to simulation conditions. As the ellipse lateral size increases, this out-of-plane precession is suppressed, due to the excitation of spatially non-uniform magnetization modes.

  8. Spin coating of electrolytes

    DOE Patents [OSTI]

    Stetter, Joseph R.; Maclay, G. Jordan

    1989-01-01

    Methods for spin coating electrolytic materials onto substrates are disclosed. More particularly, methods for depositing solid coatings of ion-conducting material onto planar substrates and onto electrodes are disclosed. These spin coating methods are employed to fabricate electrochemical sensors for use in measuring, detecting and quantifying gases and liquids.

  9. Precessional magnetization induced spin current from CoFeB into Ta

    SciTech Connect (OSTI)

    Jamali, Mahdi; Klemm, Angeline; Wang, Jian-Ping

    2013-12-16

    The spin dynamics at the interface between the CoFeB and Ta layer has been studied using spin pumping and spin wave characterizations. The spin pumping driven by the ferromagnetic resonance in the CoFeB layer injects a spin current into Ta layer which results in an electromotive force across the Ta layer due to the inverse spin Hall effect. Upon changing the polarity of the bias magnetic field, the polarity of the output voltage inverts and the output voltage increases linearly in respect to the microwave signal power which are consistent with the spin pumping characteristics. The effect of the in-plane magnetization angle on the output voltage has been studied. Furthermore, it is found that the frequency spectrum of the spin Hall voltage is modified by the annealing temperature and the full width at half maximum of the spin pumping increases by more than 40% with the increase of the annealing temperature from 200 °C to 300 °C. The spin Hall angle at the Ta-CoFeB interface is determined to be 0.014, and the damping constant of the CoFeB increases from 0.006 in pure CoFeB to 0.015 in Ta/CoFeB film.

  10. Electronic inhomogeneity and Ag:Sb imbalance of Ag1-yPb18Sb1...

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

    Levin, B.A. Cook, K. Ahn, M.G. Kanatzidis, K. Schmidt-Rohr Year: 2009 Abstract: Using magic-angle spinning 125Te and 207Pb NMR, we have discovered the presence of two phases of...

  11. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... TEM, sup 31P and sup 29Si MAS NMR, and NHsub 3-TPD, and their applications ... 31P and 29Si magic-angle spinning NMR, and NH3 temperatureprogrammed desorption, ...

  12. RECOILING SUPERMASSIVE BLACK HOLES IN SPIN-FLIP RADIO GALAXIES

    SciTech Connect (OSTI)

    Liu, F. K.; Wang Dong; Chen Xian

    2012-02-20

    Numerical relativity simulations predict that coalescence of supermassive black hole (SMBH) binaries leads not only to a spin flip but also to a recoiling of the merger remnant SMBHs. In the literature, X-shaped radio sources are popularly suggested to be candidates for SMBH mergers with spin flip of jet-ejecting SMBHs. Here we investigate the spectral and spatial observational signatures of the recoiling SMBHs in radio sources undergoing black hole spin flip. Our results show that SMBHs in most spin-flip radio sources have mass ratio q {approx}> 0.3 with a minimum possible value q{sub min} {approx_equal} 0.05. For major mergers, the remnant SMBHs can get a kick velocity as high as 2100 km s{sup -1} in the direction within an angle {approx}< 40 Degree-Sign relative to the spin axes of remnant SMBHs, implying that recoiling quasars are biased to be with high Doppler-shifted broad emission lines while recoiling radio galaxies are biased to large apparent spatial off-center displacements. We also calculate the distribution functions of line-of-sight velocity and apparent spatial off-center displacements for spin-flip radio sources with different apparent jet reorientation angles. Our results show that the larger the apparent jet reorientation angle is, the larger the Doppler-shifting recoiling velocity and apparent spatial off-center displacement will be. We investigate the effects of recoiling velocity on the dust torus in spin-flip radio sources and suggest that recoiling of SMBHs would lead to 'dust-poor' active galactic nuclei. Finally, we collect a sample of 19 X-shaped radio objects and for each object give the probability of detecting the predicted signatures of recoiling SMBH.

  13. Synchronization of spin-transfer torque oscillators by spin pumping, inverse spin Hall, and spin Hall effects

    SciTech Connect (OSTI)

    Elyasi, Mehrdad; Bhatia, Charanjit S.; Yang, Hyunsoo

    2015-02-14

    We have proposed a method to synchronize multiple spin-transfer torque oscillators based on spin pumping, inverse spin Hall, and spin Hall effects. The proposed oscillator system consists of a series of nano-magnets in junction with a normal metal with high spin-orbit coupling, and an accumulative feedback loop. We conduct simulations to demonstrate the effect of modulated charge currents in the normal metal due to spin pumping from each nano-magnet. We show that the interplay between the spin Hall effect and inverse spin Hall effect results in synchronization of the nano-magnets.

  14. Mira, another angle | Argonne Leadership Computing Facility

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

    Mira, another angle Download original image « Back to galleryItem 2

  15. Data Products from ECMWF (European Centre for Medium Range Weather Forecasts) Covering the MAGIC AMF2 Deployment

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

    Ahlgrimm, Maike

    2015-04-02

    ECMWF derived diagnostic variables over MAGIC's ship path from Los Angeles, CA and Honolulu, HI. Two dimensional (time and height) slices were extracted once the ship's exact positions were known.

  16. OPENING ANGLES OF COLLAPSAR JETS

    SciTech Connect (OSTI)

    Mizuta, Akira; Ioka, Kunihito

    2013-11-10

    We investigate the jet propagation and breakout from the stellar progenitor for gamma-ray burst (GRB) collapsars by performing two-dimensional relativistic hydrodynamic simulations and analytical modeling. We find that the jet opening angle is given by θ{sub j} ∼ 1/5Γ{sub 0} and infer the initial Lorentz factor of the jet at the central engine, Γ{sub 0}, is a few for existing observations of θ{sub j}. The jet keeps the Lorentz factor low inside the star by converging cylindrically via collimation shocks under the cocoon pressure and accelerates at jet breakout before the free expansion to a hollow-cone structure. In this new picture, the GRB duration is determined by the sound crossing time of the cocoon, after which the opening angle widens, reducing the apparent luminosity. Some bursts violating the maximum opening angle θ{sub j,{sub max}} ∼ 1/5 ∼ 12° imply the existence of a baryon-rich sheath or a long-acting jet. We can explain the slopes in both Amati and Yonetoku spectral relations using an off-centered photosphere model, if we make only one assumption that the total jet luminosity is proportional to the initial Lorentz factor of the jet. We also numerically calibrate the pre-breakout model (Bromberg et al.) for later use.

  17. Temperature dependence of the photo-induced inverse spin Hall effect in Au/InP hybrid structures

    SciTech Connect (OSTI)

    Khamari, Shailesh K. Porwal, S.; Dixit, V. K.; Sharma, T. K.

    2014-01-27

    Photo-induced Inverse Spin Hall Effect (ISHE) measurements on Au/InP hybrid structures are performed over a temperature range of 45 to 300 K. Dependence of the spin current density on the degree of circular polarization and also on the angle of incidence of laser beam confirms the ISHE origin of measured signal. The magnitude of ISHE increases with sample cooling. A numerical model based on the spin relaxation of non-equilibrium spin-polarized electrons is proposed for predicting the temperature dependence of ISHE. Our results indicate that the proposed device can be used as a spin photodetector over a wide temperature range.

  18. Spin pumping and inverse spin Hall effects—Insights for future spin-orbitronics (invited)

    SciTech Connect (OSTI)

    Zhang, Wei Jungfleisch, Matthias B.; Jiang, Wanjun; Fradin, Frank Y.; Pearson, John E.; Hoffmann, Axel; Sklenar, Joseph; Ketterson, John B.

    2015-05-07

    Quantification of spin-charge interconversion has become increasingly important in the fast-developing field of spin-orbitronics. Pure spin current generated by spin pumping acts as a sensitive probe for many bulk and interface spin-orbit effects, which has been indispensable for the discovery of many promising new spin-orbit materials. We apply spin pumping and inverse spin Hall effect experiments, as a useful metrology, and study spin-orbit effects in a variety of metals and metal interfaces. We quantify the spin Hall effects in Ir and W using the conventional bilayer structures and discuss the self-induced voltage in a single layer of ferromagnetic permalloy. Finally, we extend our discussions to multilayer structures and quantitatively reveal the spin current flow in two consecutive normal metal layers.

  19. Microscopic studies of nonlocal spin dynamics and spin transport (invited)

    SciTech Connect (OSTI)

    Adur, Rohan; Du, Chunhui; Cardellino, Jeremy; Scozzaro, Nicolas; Wolfe, Christopher S.; Wang, Hailong; Herman, Michael; Bhallamudi, Vidya P.; Pelekhov, Denis V.; Yang, Fengyuan; Hammel, P. Chris

    2015-05-07

    Understanding the behavior of spins coupling across interfaces in the study of spin current generation and transport is a fundamental challenge that is important for spintronics applications. The transfer of spin angular momentum from a ferromagnet into an adjacent normal material as a consequence of the precession of the magnetization of the ferromagnet is a process known as spin pumping. We find that, in certain circumstances, the insertion of an intervening normal metal can enhance spin pumping between an excited ferromagnetic magnetization and a normal metal layer as a consequence of improved spin conductance matching. We have studied this using inverse spin Hall effect and enhanced damping measurements. Scanned probe magnetic resonance techniques are a complementary tool in this context offering high resolution magnetic resonance imaging, localized spin excitation, and direct measurement of spin lifetimes or damping. Localized magnetic resonance studies of size-dependent spin dynamics in the absence of lithographic confinement in both ferromagnets and paramagnets reveal the close relationship between spin transport and spin lifetime at microscopic length scales. Finally, detection of ferromagnetic resonance of a ferromagnetic film using the photoluminescence of nitrogen vacancy spins in neighboring nanodiamonds demonstrates long-range spin transport between insulating materials, indicating the complexity and generality of spin transport in diverse, spatially separated, material systems.

  20. Experimental observation of magic-wavelength behavior of {sup 87}Rb atoms in an optical lattice

    SciTech Connect (OSTI)

    Lundblad, N.; Schlosser, M.; Porto, J. V.

    2010-03-15

    We demonstrate the cancellation of the differential ac Stark shift of the microwave hyperfine clock transition in trapped {sup 87}Rb atoms. Recent progress in metrology exploits so-called magic wavelengths, whereby an atomic ensemble can be trapped with laser light whose wavelength is chosen so that both levels of an optical atomic transition experience identical ac Stark shifts. Similar magic-wavelength techniques are not possible for the microwave hyperfine transitions in the alkali metals due to their simple electronic structure. We show, however, that ac Stark shift cancellation is indeed achievable for certain values of wavelength, polarization, and magnetic field. The cancellation comes at the expense of a small magnetic-field sensitivity. The technique demonstrated here has implications for experiments involving the precise control of optically trapped neutral atoms.

  1. Marine ARM GPCI Investigation of Clouds (MAGIC) Science Objectives and Significance

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

    ARM GPCI Investigation of Clouds (MAGIC) Science Objectives and Significance Every cloud in the sky begins as a tiny droplet, which forms around an even smaller particle called an aerosol particle. Some clouds produce precipitation, and some don't. The relationship between clouds, precipitation, and aerosols is very complex and very important. Scientists use data about clouds, precipitation, and aerosols to develop computer codes, or models, that simulate what's happening in the atmosphere and

  2. Microsoft Word - 20130423 AMF2_MAGIC_Safety_Appendix_for_Web.docx

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

    Native Energy and Technology, Inc. ADDENDUM - Atmospheric Radiation Measurement Program Second Mobile Facility (AMF2) Operational Support for MAGIC - HORIZON SPIRIT Date: April 30, 2013 Native Energy and Technology, Inc. 1.0 GENERAL ADMINISTRATION 1.1 Scope The purpose of this Appendix is to provide all AMF2 personnel and visitors with important health and safety information, procedures, and requirements particular to the second ARM Mobile Facility (AMF2) operations on Horizon Spirit in support

  3. Dependence of Kambersky damping on Fermi level and spin orientation

    SciTech Connect (OSTI)

    Qu, T.; Victora, R. H.

    2014-05-07

    Kambersky damping represents the loss of magnetic energy from the electrons to the lattice through the spin orbit interaction. It is demonstrated that, for bcc Fe-based transition metal alloys, the logarithm of the energy loss is proportional to the density of states at the Fermi level. Both inter and intraband damping are calculated for spins at arbitrary angle to the previously examined [001] direction. Although the easy axis 〈100〉 shows isotropic relaxation and achieves the minimum damping value of 0.002, other directions, such as 〈110〉, show substantial anisotropic damping.

  4. Spinning fluids reactor

    DOE Patents [OSTI]

    Miller, Jan D; Hupka, Jan; Aranowski, Robert

    2012-11-20

    A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

  5. Spin filter and spin valve in ferromagnetic graphene

    SciTech Connect (OSTI)

    Song, Yu Dai, Gang

    2015-06-01

    We propose and demonstrate that a EuO-induced and top-gated graphene ferromagnetic junction can be simultaneously operated as a spin filter and a spin valve. We attribute such a remarkable result to a coexistence of a half-metal band and a common energy gap for opposite spins in ferromagnetic graphene. We show that both the spin filter and the spin valve can be effectively controlled by a back gate voltage, and they survive for practical metal contacts and finite temperature. Specifically, larger single spin currents and on-state currents can be reached with contacts with work functions similar to graphene, and the spin filter can operate at higher temperature than the spin valve.

  6. Spin Wave Genie

    Energy Science and Technology Software Center (OSTI)

    2015-02-16

    The four-dimensional scattering function S(Q,w) obtained by inelastic neutron scattering measurements provides unique "dynamical fingerprints" of the spin state and interactions present in complex magnetic materials. Extracting this information however is currently a slow and complex process that may take an expert -depending on the complexity of the system- up to several weeks of painstaking work to complete. Spin Wave Genie was created to abstract and automate this process. It strives to both reduce themore » time to complete this analysis and make these calculations more accessible to a broader group of scientists and engineers.« less

  7. Overview of Processes Involved in Spin Transfer Collisions

    SciTech Connect (OSTI)

    Buttimore, N. H.

    2008-04-30

    An outline is provided of methods for polarizing antiprotons that include the possible use of channelling in a bent crystal and also the technique of scattering off leptons or protons at a suitably small angle. In the method of channelling it is suggested that the angular dependence of the analysing power of the incident particle is cubic in the angle for single scattering in the crystal when this takes place within the region of electromagnetic hadronic interference as is most likely for channelled particles. Polarization transfer in the scattering of antiprotons off leptons or protons is discussed in addition where emphasis is laid on the angular integrals over spin observables appropriate for spin filtering.

  8. Manipulating topological states by imprinting non-collinear spin textures

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

    Streubel, Robert; Han, Luyang; Im, Mi -Young; Kronast, Florian; Rößler, Ulrich K.; Radu, Florin; Abrudan, Radu; Lin, Gungun; Schmidt, Oliver G.; Fischer, Peter; et al

    2015-03-05

    Topological magnetic states, such as chiral skyrmions, are of great scientific interest and show huge potential for novel spintronics applications, provided their topological charges can be fully controlled. So far skyrmionic textures have been observed in noncentrosymmetric crystalline materials with low symmetry and at low temperatures. We propose theoretically and demonstrate experimentally the design of spin textures with topological charge densities that can be tailored at ambient temperatures. Tuning the interlayer coupling in vertically stacked nanopatterned magnetic heterostructures, such as a model system of a Co/Pd multilayer coupled to Permalloy, the in-plane non-collinear spin texture of one layer can bemore » imprinted into the out-of-plane magnetised material. We observe distinct spin textures, e.g. vortices, magnetic swirls with tunable opening angle, donut states and skyrmion core configurations. We show that applying a small magnetic field, a reliable switching between topologically distinct textures can be achieved at remanence« less

  9. Spin Transport in Semiconductor heterostructures

    SciTech Connect (OSTI)

    Domnita Catalina Marinescu

    2011-02-22

    The focus of the research performed under this grant has been the investigation of spin transport in magnetic semiconductor heterostructures. The interest in these systems is motivated both by their intriguing physical properties, as the physical embodiment of a spin-polarized Fermi liquid, as well as by their potential applications as spintronics devices. In our work we have analyzed several different problems that affect the spin dynamics in single and bi-layer spin-polarized two-dimensional (2D) systems. The topics of interests ranged from the fundamental aspects of the electron-electron interactions, to collective spin and charge density excitations and spin transport in the presence of the spin-orbit coupling. The common denominator of these subjects is the impact at the macroscopic scale of the spin-dependent electron-electron interaction, which plays a much more subtle role than in unpolarized electron systems. Our calculations of several measurable parameters, such as the excitation frequencies of magneto-plasma modes, the spin mass, and the spin transresistivity, propose realistic theoretical estimates of the opposite-spin many-body effects, in particular opposite-spin correlations, that can be directly connected with experimental measurements.

  10. ''Magic'' Energies for Detecting Light Elements with Resonant Alpha Particle Backscattering

    SciTech Connect (OSTI)

    Wetteland, C.J.; Maggiore, C.J.; Tesmer, J.R.; He, X-M.; Lee, D-H.

    1998-11-04

    Resonant backscattering is widely used to improve the detection limit of the light elements such as B, C, N and O. One disadvantage, however, is that several incident energies are normally needed if the sample contains a number of the light elements. There are ''magic'' energies at which several light elements can be detected simultaneously with suitable sensitivities. When these energies are used along with the elastic recoil detection of hydrogen, multiple elements can be detected without changing the beam energy, and the analysis time is greatly reduced. These reactions along with examples will be discussed.

  11. Angular dependence of the spin textures in two-dimensional chiral magnets

    SciTech Connect (OSTI)

    Tang, Dan; Qi, Yang

    2015-05-28

    The angular dependence of spin textures in thin helimagnetic films is investigated by a Monte Carlo simulation. When an external field is applied at an angle relative to the film normal, we find that the skyrmion states with broken axis-symmetric structure are able to persist over a wide range of angles by changing the spin orientation. In addition, the uniaxial anisotropy is able to stabilize the distorted skyrmions. This behavior reflects the robust topological stability of skyrmion states in helimagnets and favors their application in spintronic devices.

  12. Measurement of the Kerr spin parameter by observation of a compact object's shadow

    SciTech Connect (OSTI)

    Hioki, Kenta; Maeda, Kei-ichi

    2009-07-15

    A black hole casts a shadow as an optical appearance because of its strong gravitational field. We study how to determine the spin parameter and the inclination angle by observing the apparent shape of the shadow, which is distorted mainly by those two parameters. Defining some observables characterizing the apparent shape (its radius and distortion parameter), we find that the spin parameter and inclination angle of a Kerr black hole can be determined by the observation. This technique is also extended to the case of a Kerr naked singularity.

  13. State diagram of an orthogonal spin transfer spin valve device

    SciTech Connect (OSTI)

    Ye, Li; Wolf, Georg; Pinna, Daniele; Chaves-O'Flynn, Gabriel D.; Kent, Andrew D.

    2015-05-21

    We present the switching characteristics of a spin-transfer device that incorporates a perpendicularly magnetized spin-polarizing layer with an in-plane magnetized free and fixed magnetic layer, known as an orthogonal spin transfer spin valve device. This device shows clear switching between parallel (P) and antiparallel (AP) resistance states and the reverse transition (AP → P) for both current polarities. Further, hysteretic transitions are shown to occur into a state with a resistance intermediate between that of the P and AP states, again for both current polarities. These unusual spin-transfer switching characteristics can be explained within a simple macrospin model that incorporates thermal fluctuations and considers a spin-polarized current that is tilted with respect to the free layer's plane, due to the presence of the spin-transfer torque from the polarizing layer.

  14. Spin Hall controlled magnonic microwaveguides

    SciTech Connect (OSTI)

    Demidov, V. E.; Urazhdin, S.; Rinkevich, A. B.; Reiss, G.; Demokritov, S. O.

    2014-04-14

    We use space-resolved magneto-optical spectroscopy to study the influence of spin Hall effect on the excitation and propagation of spin waves in microscopic magnonic waveguides. We find that the spin Hall effect not only increases the spin-wave propagation length, but also results in an increased excitation efficiency due to the increase of the dynamic susceptibility in the vicinity of the inductive antenna. We show that the efficiency of the propagation length enhancement is strongly dependant on the type of the excited spin-wave mode and its wavelength.

  15. RHIC spin flipper commissioning results

    SciTech Connect (OSTI)

    Bai M.; Roser, T.; Dawson, C.; Kewisch, J.; Makdisi, Y.; Oddo, P.; Pai, C.; Pile, P.

    2012-05-20

    The five AC dipole RHIC spin flipper design in the RHIC Blue ring was first tested during the RHIC 2012 polarized proton operation. The advantage of this design is to eliminate the vertical coherent betatron oscillations outside the spin flipper. The closure of each ac dipole vertical bump was measured with orbital response as well as spin. The effect of the rotating field on the spin motion by the spin flipper was also confirmed by measuring the suppressed resonance at Q{sub s} = 1 - Q{sub osc}.

  16. Integrated experimental setup for angle resolved photoemission...

    Office of Scientific and Technical Information (OSTI)

    Integrated experimental setup for angle resolved photoemission spectroscopy of transuranic materials Citation Details In-Document Search Title: Integrated experimental setup for...

  17. Detection of the Crab Pulsar above 25 GeV with the MAGIC Telescope

    SciTech Connect (OSTI)

    Shayduk, M

    2009-04-08

    The 17 m diameter Cherenkov telescope MAGIC, located on the Canary Island of La Palma, has the lowest trigger threshold among operating Cherenkov telescopes; this makes it a very promising tool for the detection of the pulsed gamma-ray ({gamma}-ray) emission from ground. Recently, a new analog summation trigger concept, which allows reducing the threshold even further, has been designed and implemented. The analog signals of patches in the camera, comprising 18 pixels each, are summed up in the analog mode. In order to prevent triggers from photomultiplier (PMT) afterpulses, the individual pixel signals are clipped at a preset amplitude level and then added up. The average FWHM of the time duration of signals induced by cosmic rays is 2.6 ns. This allows one to keep the coincidence time window very small and thus to strongly suppress accidental triggers. In the usual digital trigger designs, the signal should be above a certain threshold from each individual pixel to contribute to the trigger. In the summation trigger all low amplitude signals in a given patch in the camera are summed up and fully contribute to the trigger.The new trigger concept provides a low cost trigger for Cherenkov telescopes and it is very effective and stable. This trigger system for the MAGIC telescope was installed in October 2007 and was successfully used in the detection of the Crab Pulsar above 25 GeV.

  18. Towards a more accurate extraction of the SPICE netlist from MAGIC based layouts

    SciTech Connect (OSTI)

    Geronimo, G.D.

    1998-08-01

    The extraction of the SPICE netlist form MAGIC based layouts is investigated. It is assumed that the layout is fully coherent with the corresponding mask representation. The process of the extraction can be made in three steps: (1) extraction of .EXT file from layout, through MAGIC command extract; (2) extraction of the netlist from .EXT file through ext2spice extractor; and (3) correction of the netlist through ext2spice.corr program. Each of these steps introduces some approximations, most of which can be optimized, and some errors, most of which can be corrected. Aim of this work is the description of each step, of the approximations and errors on each step, and of the corresponding optimizations and corrections to be made in order to improve the accuracy of the extraction. The HP AMOS14TB 0.5 {micro}m process with linear capacitor and silicide block options and the corresponding SCN3MLC{_}SUBM.30.tech27 technology file will be used in the following examples.

  19. Evidence of dynamical spin shielding in Ce from spin-resolved...

    Office of Scientific and Technical Information (OSTI)

    Evidence of dynamical spin shielding in Ce from spin-resolved photoelectron spectroscopy Citation Details In-Document Search Title: Evidence of dynamical spin shielding in Ce from ...

  20. Comparison of MAGIC and Diatom paleolimnological model hindcasts of lakewater acidification in the Adirondack region of New York

    SciTech Connect (OSTI)

    Sullivan, T.J.; Bernert, J.A.; Eliers, J.M. ); Jenne, E.A. ); Cosby, B.J. . School of Forestry and Environmental Studies); Charles, D.F.; Selle, A.R. . Environmental Research Lab.)

    1991-03-01

    Thirty-three lakes that had been statistically selected as part of the US Environmental Protection Agency's Eastern Lake Survey and Direct Delayed Response Project (DDRP) were used to compare the MAGIC (watershed) and Diatom (paleolimnological) models. The study lakes represented a well-defined group of Adirondack lakes, each larger than 4 ha in area and having acid-neutralizing capacity (ANC) <400 {mu}eq L{sup {minus}1}. The study first compared current and pre-industrial (before 1850) pH and ANC estimates from Diatom and MAGIC as they were calibrated in the preceding Paleocological Investigation of Recent Lake Acidification (PIRLA) and DDRP studies, respectively. Initially, the comparison of hindcasts of pre-industrial chemistry was confounded by seasonal and methodological differences in lake chemistry data used in calibration of the model. Although certain differences proved to be of little significance for comparison, MAGIC did predict significantly higher pre-industrial ANC and pH values than did Diatom, using calibrations in the preceding studies. Both models suggest acidification of low ANC Adirondack region lakes since preindustrial times, but differ primarily in that MAGIC inferred greater acidification and that acidification has occurred in all lakes in the comparison, whereas Diatom inferred that acidification has been restricted to low ANC lakes (

  1. Inductance due to spin current

    SciTech Connect (OSTI)

    Chen, Wei

    2014-03-21

    The inductance of spintronic devices that transport charge neutral spin currents is discussed. It is known that in a media that contains charge neutral spins, a time-varying electric field induces a spin current. We show that since the spin current itself produces an electric field, this implies existence of inductance and electromotive force when the spin current changes with time. The relations between the electromotive force and the corresponding flux, which is a vector calculated by the cross product of electric field and the trajectory of the device, are clarified. The relativistic origin generally renders an extremely small inductance, which indicates the advantage of spin current in building low inductance devices. The same argument also explains the inductance due to electric dipole current and applies to physical dipoles consist of polarized bound charges.

  2. Multifrequency spin resonance in diamond

    SciTech Connect (OSTI)

    Childress, Lilian; McIntyre, Jean

    2010-09-15

    Magnetic resonance techniques provide a powerful tool for controlling spin systems, with applications ranging from quantum information processing to medical imaging. Nevertheless, the behavior of a spin system under strong excitation remains a rich dynamical problem. In this paper, we examine spin resonance of the nitrogen-vacancy center in diamond under conditions outside the regime where the usual rotating-wave approximation applies, focusing on effects of multifrequency excitation and excitation with orientation parallel to the spin quantization axis. Strong-field phenomena such as multiphoton transitions and coherent destruction of tunneling are observed in the spectra and analyzed via numerical and analytic theory. In addition to illustrating the response of a spin system to strong multifrequency excitation, these observations may inform techniques for manipulating electron-nuclear spin quantum registers.

  3. Understanding the proton's spin structure

    SciTech Connect (OSTI)

    Fred Myhrer; Thomas, Anthony W.

    2010-02-01

    We discuss the tremendous progress that has been towards an understanding of how the spin of the proton is distributed on its quark and gluon constituents. This is a problem that began in earnest twenty years ago with the discovery of the proton "spin crisis" by the European Muon Collaboration. The discoveries prompted by that original work have given us unprecedented insight into the amount of spin carried by polarized gluons and the orbital angular momentum of the quarks.

  4. Spontaneous Coherence and Spin Texture

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

    Energy Frontier Research Centers: Solid-State Lighting Science Center for Frontiers of ... Spontaneous Coherence and Spin Texture HomeEnergy ResearchEFRCsSolid-State Lighting ...

  5. Spin waves in the (

    SciTech Connect (OSTI)

    Lipscombe, O. J.; Chen, G. F.; Fang, Chen; Perring, T. G.; Abernathy, Douglas L; Christianson, Andrew D; Egami, Takeshi; Wang, Nanlin; Hu, Jiangping; Dai, Pengcheng

    2011-01-01

    We use neutron scattering to show that spin waves in the iron chalcogenide Fe{sub 1.05}Te display novel dispersion clearly different from both the first principles density functional calculations and recent observations in the related iron pnictide CaFe{sub 2}As{sub 2}. By fitting to a Heisenberg Hamiltonian, we find that although the nearest-neighbor exchange couplings in the two systems are quite different, their next-nearest-neighbor (NNN) couplings are similar. This suggests that superconductivity in the pnictides and chalcogenides share a common magnetic origin that is intimately associated with the NNN magnetic coupling between the irons.

  6. Method and sample spinning apparatus for measuring the NMR spectrum of an orientationally disordered sample

    DOE Patents [OSTI]

    Pines, Alexander; Samoson, Ago

    1990-01-01

    An improved NMR apparatus and method are described which substantially improve the resolution of NMR measurements made on powdered or amorphous or otherwise orientationally disordered samples. The apparatus spins the sample about an axis. The angle of the axis is mechanically varied such that the time average of two or more Legendre polynomials are zero.

  7. Angle-resolved spin wave band diagrams of square antidot lattices...

    Office of Scientific and Technical Information (OSTI)

    (IOM-CNR), Sede di Perugia, co Dipartimento di Fisica e Geologia, Via A. Pascoli, I-06123 Perugia (Italy) Dipartimento di Fisica e Scienze della Terra, Universit di Ferrara, ...

  8. Strongly enhanced spin current in topological insulator/ferromagnetic metal heterostructures by spin pumping

    SciTech Connect (OSTI)

    Wu, C. N.; Hung, H. Y.; Lin, H. Y.; Lin, P. H.; Kwo, J. E-mail: raynien@phys.nthu.edu.tw; Lin, Y. H.; Fanchiang, Y. T.; Hong, M. E-mail: raynien@phys.nthu.edu.tw; Lin, J. G.; Lee, S. F.

    2015-05-07

    Spin pumping effect in Bi{sub 2}Se{sub 3}/Fe{sub 3}Si and Fe/Bi{sub 2}Te{sub 3} heterostructures was studied. High quality films of Bi{sub 2}Se{sub 3}(001) on ferromagnetic Fe{sub 3}Si(111) layer and Fe(111) films on Bi{sub 2}Te{sub 3}(001) layer were grown epitaxially by molecular beam epitaxy. Using a microwave cavity source, large voltages due to the Inverse Spin Hall Effect (V{sub ISHE}) were detected in Bi{sub 2}Se{sub 3}(001)/Fe{sub 3}Si(111) bi-layer at room temperature. V{sub ISHE} of up to 63.4 ± 4.0 μV at 100 mW microwave power (P{sub MW}) was observed. In addition, Fe(111)/Bi{sub 2}Te{sub 3}(001) bi-layer also showed a large V{sub ISHE} of 3.0 ± 0.1 μV at P{sub MW} of 25 mW. V{sub ISHE} of both structures showed microwave linear power dependence in accordance with the theoretical model of spin pumping. The spin Hall angle was calculated to be 0.0053 ± 0.002 in Bi{sub 2}Se{sub 3} and was estimated to be 0.0068 ± 0.003 in Bi{sub 2}Te{sub 3}. The charge current density (J{sub c}) of Bi{sub 2}Se{sub 3}/Fe{sub 3}Si and Fe/Bi{sub 2}Te{sub 3} structures are comparable and are about 2–5 times higher than the Fe{sub 3}Si/normal metal and Fe{sub 3}Si/GaAs results. The significant enhancement of spin current in topological insulator/ferromagnetic metal (TI/FM) and FM/TI bilayers is attributed to strong spin-orbit coupling inherent of TIs and demonstrates the high potential of exploiting TI-based structures for spintronic applications.

  9. Determination of the Pt spin diffusion length by spin-pumping and spin Hall effect

    SciTech Connect (OSTI)

    Zhang, Wei; Pearson, John E.; Hoffmann, Axel; Vlaminck, Vincent; Divan, Ralu; Bader, Samuel D.

    2013-12-09

    The spin diffusion length of Pt at room temperature and at 8 K is experimentally determined via spin pumping and spin Hall effect in permalloy/Pt bilayers. Voltages generated during excitation of ferromagnetic resonance from the inverse spin Hall effect and anisotropic magnetoresistance effect were investigated with a broadband approach. Varying the Pt layer thickness gives rise to an evolution of the voltage line shape due to the superposition of the above two effects. By studying the ratio of the two voltage components with the Pt layer thickness, the spin diffusion length of Pt can be directly extracted. We obtain a spin diffusion length of ∼1.2 nm at room temperature and ∼1.6 nm at 8 K.

  10. Observation of the inverse spin Hall effect in ZnO thin films: An all-electrical approach to spin injection and detection

    SciTech Connect (OSTI)

    Prestgard, Megan C.; Tiwari, Ashutosh

    2014-03-24

    The inverse spin Hall effect (ISHE) is a newly discovered, quantum mechanical phenomenon where an applied spin current results in the generation of an electrical voltage in the transverse direction. It is anticipated that the ISHE can provide a more simple way of measuring spin currents in spintronic devices. The ISHE was first observed in noble metals that exhibit strong spin-orbit coupling. However, recently, the ISHE has been detected in conventional semiconductors (such as Si and Ge), which possess weak spin-orbit coupling. This suggests that large-spin orbit coupling is not a requirement for observing the ISHE. In this paper, we are reporting the observation of the ISHE in an alternative semiconductor material, zinc oxide (ZnO) using all-electrical means. In our study, we found that when a spin-polarized current is injected into the ZnO film from a NiFe ferromagnetic injector via an MgO tunnel barrier layer, a voltage transverse to both the direction of the current as well as its spin-polarization is generated in the ZnO layer. The polarity of this voltage signal was found to flip on reversing the direction of the injected current as well as on reversing the polarization of the current, consistent with the predictions of the ISHE process. Through careful analysis of the ISHE data, we determined a spin-Hall angle of approximately 1.651 × 10{sup −2} for ZnO, which is two orders of magnitude higher than that of silicon. Observation of a detectable room-temperature ISHE signal in ZnO via electrical injection and detection is a groundbreaking step that opens a path towards achieving transparent spin detectors for next-generation spintronic device technology.

  11. Tensor spin observables and spin stucture at low Q2

    SciTech Connect (OSTI)

    Slifer, Karl J.

    2015-04-01

    We discuss recent spin structure results from Jefferson Lab, and outline an emerging program to study tensor spin observables using solid deuteron targets. These new experiments open the potential to study hidden color, the tensor nature of short range correlations, and to probe for exotic gluonic states.

  12. Heterogeneity of functional groups in a metal-organic framework displays magic number ratios

    SciTech Connect (OSTI)

    Sue, Andrew C.-H.; Mannige, Ranjan V.; Deng, Hexiang; Cao, Dennis; Wang, Cheng; Gándara, Felipe; Stoddart, J. Fraser; Whitelam, Stephen; Yaghi, Omar M.

    2015-05-20

    Multiple organic functionalities can now be apportioned into nanoscale domains within a metal-coordinated framework, posing the following question: how do we control the resulting combination of “heterogeneity and order”? Here, we report the creation of a metal–organic framework, MOF-2000, whose two component types are incorporated in a 2:1 ratio, even when the ratio of component types in the starting solution is varied by an order of magnitude. Statistical mechanical modeling suggests that this robust 2:1 ratio has a nonequilibrium origin, resulting from kinetic trapping of component types during framework growth. Our simulations show how other “magic number” ratios of components can be obtained by modulating the topology of a framework and the noncovalent interactions between component types, a finding that may aid the rational design of functional multicomponent materials.

  13. Spin injection and spin transport in paramagnetic insulators

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

    Okamoto, Satoshi

    2016-02-22

    We investigate the spin injection and the spin transport in paramagnetic insulators described by simple Heisenberg interactions using auxiliary particle methods. Some of these methods allow access to both paramagnetic states above magnetic transition temperatures and magnetic states at low temperatures. It is predicted that the spin injection at an interface with a normal metal is rather insensitive to temperatures above the magnetic transition temperature. On the other hand below the transition temperature, it decreases monotonically and disappears at zero temperature. We also analyze the bulk spin conductance. We show that the conductance becomes zero at zero temperature as predictedmore » by linear spin wave theory but increases with temperature and is maximized around the magnetic transition temperature. These findings suggest that the compromise between the two effects determines the optimal temperature for spintronics applications utilizing magnetic insulators.« less

  14. Spin noise spectroscopy of ZnO

    SciTech Connect (OSTI)

    Horn, H.; Berski, F.; Hbner, J.; Oestreich, M.; Balocchi, A.; Marie, X.; Mansur-Al-Suleiman, M.; Bakin, A.; Waag, A.

    2013-12-04

    We investigate the thermal equilibrium dynamics of electron spins bound to donors in nanoporous ZnO by optical spin noise spectroscopy. The spin noise spectra reveal two noise contributions: A weak spin noise signal from undisturbed localized donor electrons with a dephasing time of 24 ns due to hyperfine interaction and a strong spin noise signal with a spin dephasing time of 5 ns which we attribute to localized donor electrons which interact with lattice defects.

  15. Quantification of the spin-Hall anti-damping torque with a resonance spectrometer

    SciTech Connect (OSTI)

    Emori, Satoru Nan, Tianxiang; Oxholm, Trevor M.; Boone, Carl T.; Sun, Nian X.; Jones, John G.; Howe, Brandon M.; Brown, Gail J.; Budil, David E.

    2015-01-12

    We present a simple technique using a cavity-based resonance spectrometer to quantify the anti-damping torque due to the spin Hall effect. Modification of ferromagnetic resonance is observed as a function of small DC current in sub-mm-wide strips of bilayers, consisting of magnetically soft FeGaB and strong spin-Hall metal Ta. From the detected current-induced linewidth change, we obtain an effective spin Hall angle of 0.08–0.09 independent of the magnetic layer thickness. Our results demonstrate that a sensitive resonance spectrometer can be a general tool to investigate spin Hall effects in various material systems, even those with vanishingly low conductivity and magnetoresistance.

  16. Azimuthal angle dependence of dijet production in unpolarized hadron scattering

    SciTech Connect (OSTI)

    Lu Zhun; Schmidt, Ivan [Departamento de Fisica, Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile) and Center of Subatomic Physics, Valparaiso (Chile)

    2008-08-01

    We study the azimuthal angular dependence of back-to-back dijet production in unpolarized hadron scattering H{sub A}+H{sub B}{yields}J{sub 1}+J{sub 2}+X, arising from the product of two Boer-Mulders functions, which describe the transverse spin distribution of quarks inside an unpolarized hadron. We find that when the dijet is of two identical quarks (J{sub q}+J{sub q}) or a quark-antiquark pair (J{sub q}+J{sub q}), there is a cos{delta}{phi} angular dependence of the dijet, with {delta}{phi}={phi}{sub 1}-{phi}{sub 2}, and {phi}{sub 1} and {phi}{sub 2} are the azimuthal angles of the two individual jets. In the case of J{sub q}+J{sub q} production, we find that there is a color factor enhancement in the gluonic cross section, compared with the result from the standard generalized parton model. We estimate the cos{delta}{phi} asymmetry of dijet production at RHIC, showing that the color factor enhancement in the angular dependence of J{sub q}+J{sub q} production will reverse the sign of the asymmetry.

  17. Small Angle X-Ray Scattering Detector

    DOE Patents [OSTI]

    Hessler, Jan P.

    2004-06-15

    A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., qmax/qmin approx=lO0.

  18. Putting the Spin on Graphite: Observing the Spins of Impurity...

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

    With the recent advance of "spintronics" - an area of science and technology which proposes to use the spin of electrons to store and process information instead of their charge as ...

  19. Spin-manipulating polarized deuterons

    SciTech Connect (OSTI)

    Morozov, V S; Krisch, A D; Leonova, M A; Raymond, R S; Sivers, D W; Wong, V K; Hinterberger, F; Kondratenko, A M; Stephenson, E J

    2011-03-01

    Spin dynamics of polarized deuteron beams near depolarization resonances, including a new polarization preservation concept based on specially-designed multiple resonance crossings, has been tested in a series of experiments in the COSY synchrotron. Intricate spin dynamics with sophisticated pre-programmed patterns as well as effects of multiple crossings of a resonance were studied both theoretically and experimentally with excellent agreement. Possible applications of these results to preserve, manipulate and spin-flip polarized beams in synchrotrons and storage rings are discussed.

  20. Geometric phase for collinear conical intersections. I. Geometric phase angle and vector potentials

    SciTech Connect (OSTI)

    Li Xuan; Brue, Daniel A.; Blandon, Juan D.; Parker, Gregory A.; Kendrick, Brian K.

    2011-02-14

    We present a method for properly treating collinear conical intersections in triatomic systems. The general vector potential (gauge theory) approach for including the geometric phase effects associated with collinear conical intersections in hyperspherical coordinates is presented. The current study develops an introductory method in the treatment of collinear conical intersections by using the phase angle method. The geometric phase angle, {eta}, in terms of purely internal coordinates is derived using the example of a spin-aligned quartet lithium triatomic system. A numerical fit and thus an analytical form for the associated vector potentials are explicitly derived for this triatomic A{sub 3} system. The application of this methodology to AB{sub 2} and ABC systems is also discussed.

  1. Polarization transfer in wide-angle Compton scattering and single-pion photoproduction from the proton

    SciTech Connect (OSTI)

    Fanelli, Cristiano V.

    2015-10-06

    Wide-angle exclusive Compton scattering and single-pion photoproduction from the proton have been investigated via measurement of the polarization transfer from a circularly polarized photon beam to the recoil proton. The WACS polarization transfer was analyzed at an incident photon energy of 3.7 GeV at a proton scattering angle of θPcm = 70°. The longitudinal transfer KLL, measured to be 0.645 ± 0.059 ± 0.048, where the first error is statistical and the second is systematic, has the same sign as predicted for the reaction mechanism in which the photon interacts with a single quark carrying the spin of the proton. However, the observed value is ~3 times larger than predicted by the GPD-based calculations, which indicates a significant unknown contribution to the scattering amplitude.

  2. Polarization transfer in wide-angle Compton scattering and single-pion photoproduction from the proton

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

    Fanelli, Cristiano V.

    2015-10-06

    Wide-angle exclusive Compton scattering and single-pion photoproduction from the proton have been investigated via measurement of the polarization transfer from a circularly polarized photon beam to the recoil proton. The WACS polarization transfer was analyzed at an incident photon energy of 3.7 GeV at a proton scattering angle of θPcm = 70°. The longitudinal transfer KLL, measured to be 0.645 ± 0.059 ± 0.048, where the first error is statistical and the second is systematic, has the same sign as predicted for the reaction mechanism in which the photon interacts with a single quark carrying the spin of the proton.more » However, the observed value is ~3 times larger than predicted by the GPD-based calculations, which indicates a significant unknown contribution to the scattering amplitude.« less

  3. Chemical synthesis and optical characterization of regular and magic-sized CdS quantum dot nanocrystals using 1-dodecanethiol

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

    Dickson, Rachel E.; Hu, Michael Z.

    2015-03-23

    In this study, cadmium sulfide (CdS) quantum dot (QD) nanoparticles have been synthesized using a one-pot noninjection reaction procedure in solvent medium 1-octadecene. This approach used a cadmium salt and 1-dodecanethiol, an organic sulfur, as the cadmium and sulfur sources, respectively, along with a long-chain organic acid (myristic acid, lauric acid, or stearic acid). The acid has dual effects as a surface capping ligand and a solubility controlling agent as well. UV–Vis and photoluminescence (PL) spectrometry techniques were used to characterize the optical properties, along with transmission electron microscopy (TEM) to identify the structure and size. Our newly developed synthesismore » procedure allowed for investigation of both regular and “magic-sized” CdS QDs by systematically controlling reaction parameters such as reactant type, reactant concentration, and reaction temperature. The organic sulfur (1-dodecanethiol) proved to be a useful sulfur source for synthesizing magic-sized CdS QDs, previously unreported. Several distinctive size regimes of magic-sized quantum dots (MSQDs), including Families 378 and 407, were successfully produced by controlling a small number of factors. Finally, the understanding of controlled Cd release in a MSQD formation mechanism is developed.« less

  4. Rotatable spin-polarized electron source for inverse-photoemission experiments

    SciTech Connect (OSTI)

    Stolwijk, S. D. Wortelen, H.; Schmidt, A. B.; Donath, M.

    2014-01-15

    We present a ROtatable Spin-polarized Electron source (ROSE) for the use in spin- and angle-resolved inverse-photoemission (SR-IPE) experiments. A key feature of the ROSE is a variable direction of the transversal electron beam polarization. As a result, the inverse-photoemission experiment becomes sensitive to two orthogonal in-plane polarization directions, and, for nonnormal electron incidence, to the out-of-plane polarization component. We characterize the ROSE and test its performance on the basis of SR-IPE experiments. Measurements on magnetized Ni films on W(110) serve as a reference to demonstrate the variable spin sensitivity. Moreover, investigations of the unoccupied spin-dependent surface electronic structure of Tl/Si(111) highlight the capability to analyze complex phenomena like spin rotations in momentum space. Essentially, the ROSE opens the way to further studies on complex spin-dependent effects in the field of surface magnetism and spin-orbit interaction at surfaces.

  5. Stacking order dependence of inverse spin Hall effect and anomalous Hall effect in spin pumping experiments

    SciTech Connect (OSTI)

    Kim, Sang-Il; Seo, Min-Su; Park, Seung-Young; Kim, Dong-Jun; Park, Byong-Guk

    2015-05-07

    The dependence of the measured DC voltage on the non-magnetic material (NM) in NM/CoFeB and CoFeB/NM bilayers is studied under ferromagnetic resonance conditions in a TE{sub 011} resonant cavity. The directional change of the inverse spin Hall effect (ISHE) voltage V{sub ISHE} for the stacking order of the bilayer can separate the pure V{sub ISHE} and the anomalous Hall effect (AHE) voltage V{sub AHE} utilizing the method of addition and subtraction. The Ta and Ti NMs show a broad deviation of the spin Hall angle θ{sub ISH}, which originates from the AHE in accordance with the high resistivity of NMs. However, the Pt and Pd NMs show that the kinds of NMs with low resistivity are consistent with the previously reported θ{sub ISH} values. Therefore, the characteristics that NM should simultaneously satisfy to obtain a reasonable V{sub ISHE} value in bilayer systems are large θ{sub ISH} and low resistivity.

  6. Influence of electron-phonon interaction on soliton mediated spin-charge conversion effects in two-component polymer model

    SciTech Connect (OSTI)

    Sergeenkov, S. Moraes, F.; Furtado, C.; Araujo-Moreira, F.M.

    2010-02-15

    By mapping a Hubbard-like model describing a two-component polymer in the presence of strong enough electron-phonon interactions ({kappa}) onto the system of two coupled nonlinear Schroedinger equations with U(2) symmetry group, some nontrivial correlations between topological solitons mediated charge Q and spin S degrees of freedom are obtained. Namely, in addition to a charge fractionalization and reentrant like behavior of both Q({kappa}) and S({kappa}), the model also predicts a decrease of soliton velocity with {kappa} as well as spin-charge conversion effects which manifest themselves through an explicit S(Q,{omega}) dependence (with {omega} being a mixing angle between spin-up and spin-down electron amplitudes). A possibility to observe the predicted effects in low-dimensional systems with charge and spin soliton carriers is discussed.

  7. Heat generation by electronic current in a quantum dot spin-valve

    SciTech Connect (OSTI)

    Chi, Feng; Sun, Lian-Liang; Guo, Yu

    2014-10-28

    Electric-current-induced heat generation in an interacting single-level quantum dot connected to ferromagnetic leads with noncollinear magnetizations is theoretically investigated. We find that when the two leads' spin polarization rates are identical and much smaller than unit, the magnitude of the heat generation is almost monotonously enhanced as the angle between the leads' magnetic moments is varied from zero to π, while the magnitude of the electric current is continuously suppressed. Moreover, the properties of the heat generation depend on the lead's spin polarization rate in different ways when the angle is varied. If at least one of the leads' spin polarization rate approaches to unit, the spin-valve effect of the heat generation is identical to that of the electric current. Now the previously found negative differential of the heat generation disappears when the angle approaches to π. As compared to the current, the heat generation is more sensitive to the system's asymmetry when one of the electrodes is half-metallic in noncollinear configurations.

  8. Kinetics of spin relaxation in quantum wires and channels: Boundary spin echo and formation of a persistent spin helix

    SciTech Connect (OSTI)

    Slipko, Valeriy A.; Pershin, Yuriy V.

    2011-10-15

    In this paper we use a spin kinetic equation to study spin-polarization dynamics in one-dimensional (1D) wires and 2D channels. The spin kinetic equation is valid in both diffusive and ballistic spin transport regimes and therefore is more general than the usual spin drift-diffusion equations. In particular, we demonstrate that in infinite 1D wires with Rashba spin-orbit interaction the exponential spin-relaxation decay can be modulated by an oscillating function. In the case of spin relaxation in finite length 1D wires, it is shown that an initially homogeneous spin polarization spontaneously transforms into a persistent spin helix. We find that a propagating spin-polarization profile reflects from a system boundary and returns back to its initial position similarly to the reflectance of sound waves from an obstacle. The Green's function of the spin kinetic equation is derived for both finite and infinite 1D systems. Moreover, we demonstrate explicitly that the spin relaxation in specifically oriented 2D channels with Rashba and Dresselhaus spin-orbit interactions of equal strength occurs similarly to that in 1D wires of finite length. Finally, a simple transformation mapping 1D spin kinetic equation into the Klein-Gordon equation with an imaginary mass is found thus establishing an interesting connection between semiconductor spintronics and relativistic quantum mechanics.

  9. Superconducting magnetic Wollaston prism for neutron spin encoding

    SciTech Connect (OSTI)

    Li, F., E-mail: fankli@indiana.edu; Parnell, S. R.; Wang, T.; Baxter, D. V. [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States)] [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States); Hamilton, W. A. [Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States)] [Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States); Maranville, B. B. [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)] [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Semerad, R. [Ceraco Ceramic Coating GmbH, Ismaning 85737 (Germany)] [Ceraco Ceramic Coating GmbH, Ismaning 85737 (Germany); Cremer, J. T. [Adelphi Technology Inc., Redwood City, California 94063 (United States)] [Adelphi Technology Inc., Redwood City, California 94063 (United States); Pynn, R. [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States) [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States); Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States)

    2014-05-15

    A magnetic Wollaston prism can spatially split a polarized neutron beam into two beams with different neutron spin states, in a manner analogous to an optical Wollaston prism. Such a Wollaston prism can be used to encode the trajectory of neutrons into the Larmor phase associated with their spin degree of freedom. This encoding can be used for neutron phase-contrast radiography and in spin echo scattering angle measurement (SESAME). In this paper, we show that magnetic Wollaston prisms with highly uniform magnetic fields and low Larmor phase aberration can be constructed to preserve neutron polarization using high temperature superconducting (HTS) materials. The Meissner effect of HTS films is used to confine magnetic fields produced electromagnetically by current-carrying HTS tape wound on suitably shaped soft iron pole pieces. The device is cooled to ?30 K by a closed cycle refrigerator, eliminating the need to replenish liquid cryogens and greatly simplifying operation and maintenance. A HTS film ensures that the magnetic field transition within the prism is sharp, well-defined, and planar due to the Meissner effect. The spin transport efficiency across the device was measured to be ?98.5% independent of neutron wavelength and energizing current. The position-dependent Larmor phase of neutron spins was measured at the NIST Center for Neutron Research facility and found to agree well with detailed simulations. The phase varies linearly with horizontal position, as required, and the neutron beam shows little depolarization. Consequently, the device has advantages over existing devices with similar functionality and provides the capability for a large neutron beam (20 mm 30 mm) and an increase in length scales accessible to SESAME to beyond 10 ?m. With further improvements of the external coupling guide field in the prototype device, a larger neutron beam could be employed.

  10. Spin transport in normal metal/insulator/topological insulator coupled to ferromagnetic insulator structures

    SciTech Connect (OSTI)

    Kondo, Kenji

    2014-05-07

    In this study, we investigate the spin transport in normal metal (NM)/insulator (I)/topological insulator (TI) coupled to ferromagnetic insulator (FI) structures. In particular, we focus on the barrier thickness dependence of the spin transport inside the bulk gap of the TI with FI. The TI with FI is described by two-dimensional (2D) Dirac Hamiltonian. The energy profile of the insulator is assumed to be a square with barrier height V and thickness d along the transport-direction. This structure behaves as a tunnel device for 2D Dirac electrons. The calculation is performed for the spin conductance with changing the barrier thickness and the components of magnetization of FI layer. It is found that the spin conductance decreases with increasing the barrier thickness. Also, the spin conductance is strongly dependent on the polar angle ?, which is defined as the angle between the axis normal to the FI and the magnetization of FI layer. These results indicate that the structures are promising candidates for novel tunneling magnetoresistance devices.

  11. MagicPlate-512: A 2D silicon detector array for quality assurance of stereotactic motion adaptive radiotherapy

    SciTech Connect (OSTI)

    Petasecca, M. Newall, M. K.; Aldosari, A. H.; Fuduli, I.; Espinoza, A. A.; Porumb, C. S.; Guatelli, S.; Metcalfe, P.; Lerch, M. L. F.; Rosenfeld, A. B.; Booth, J. T.; Colvill, E.; Duncan, M.; Cammarano, D.; Carolan, M.; Oborn, B.; Perevertaylo, V.; Keall, P. J.

    2015-06-15

    Purpose: Spatial and temporal resolutions are two of the most important features for quality assurance instrumentation of motion adaptive radiotherapy modalities. The goal of this work is to characterize the performance of the 2D high spatial resolution monolithic silicon diode array named “MagicPlate-512” for quality assurance of stereotactic body radiation therapy (SBRT) and stereotactic radiosurgery (SRS) combined with a dynamic multileaf collimator (MLC) tracking technique for motion compensation. Methods: MagicPlate-512 is used in combination with the movable platform HexaMotion and a research version of radiofrequency tracking system Calypso driving MLC tracking software. The authors reconstruct 2D dose distributions of small field square beams in three modalities: in static conditions, mimicking the temporal movement pattern of a lung tumor and tracking the moving target while the MLC compensates almost instantaneously for the tumor displacement. Use of Calypso in combination with MagicPlate-512 requires a proper radiofrequency interference shielding. Impact of the shielding on dosimetry has been simulated by GEANT4 and verified experimentally. Temporal and spatial resolutions of the dosimetry system allow also for accurate verification of segments of complex stereotactic radiotherapy plans with identification of the instant and location where a certain dose is delivered. This feature allows for retrospective temporal reconstruction of the delivery process and easy identification of error in the tracking or the multileaf collimator driving systems. A sliding MLC wedge combined with the lung motion pattern has been measured. The ability of the MagicPlate-512 (MP512) in 2D dose mapping in all three modes of operation was benchmarked by EBT3 film. Results: Full width at half maximum and penumbra of the moving and stationary dose profiles measured by EBT3 film and MagicPlate-512 confirm that motion has a significant impact on the dose distribution. Motion

  12. Monitoring of Bright Blazars with MAGIC in the 2007/2008 Season

    SciTech Connect (OSTI)

    Satalecka, Konstancja; Bernardini, Elisa; Majumdar, Pratik; Hsu, Ching-Cheng; Galante, Nicola; Goebel, Florian; Wagner, Robert; Bonnoli, Giacomo; Stamerra, Antonio; Lindfors, Elina

    2009-04-08

    Because of the short duty-cycles and observation-time constraints, studies of bright TeV (E>100 GeV) blazars are mostly restricted to flaring episodes or rather short (days to few weeks) multiwavelength campaigns. At the same time, long-term studies of these objects are essential to gain a more complete understanding of the blazar phenomenon and to constrain theoretical models concerning jet physics. Only unbiased long-term studies are adequate for the determination of flaring state probabilities and for estimating the statistical significance of possible correlations between TeV flaring states and other wavebands or observables, such as neutrino events. Regular observations also provide triggers for multiwavelength ToO observations originating from the TeV waveband. These are particularly needed to identify and study orphan TeV flares, i.e. flares without counterparts in other wavebands. In 2007/8 the MAGIC telescope has monitored three TeV blazars on a regular basis: Mrk 501, Mrk 421, and 1ES 1959+650. We present preliminary results of these observations including the measured light curves and a correlation study for VHE {gamma}-rays and X-rays and VHE {gamma}-rays and optical R-band for Mrk 421.

  13. Optimized dark matter searches in deep observations of Segue 1 with MAGIC

    SciTech Connect (OSTI)

    Aleksi?, J.; Blanch, O.; Ansoldi, S.; Antonelli, L.A.; Bonnoli, G.; Antoranz, P.; Babic, A.; Bangale, P.; De Almeida, U. Barres; Bock, R.K.; Borracci, F.; Barrio, J.A.; Bonnefoy, S.; Gonzlez, J. Becerra; Berger, K.; Bednarek, W.; Bernardini, E.; Biland, A.; Bretz, T.; Carmona, E. E-mail: jrico@ifae; and others

    2014-02-01

    We present the results of stereoscopic observations of the satellite galaxy Segue 1 with the MAGIC Telescopes, carried out between 2011 and 2013. With almost 160 hours of good-quality data, this is the deepest observational campaign on any dwarf galaxy performed so far in the very high energy range of the electromagnetic spectrum. We search this large data sample for signals of dark matter particles in the mass range between 100 GeV and 20 TeV. For this we use the full likelihood analysis method, which provides optimal sensitivity to characteristic gamma-ray spectral features, like those expected from dark matter annihilation or decay. In particular, we focus our search on gamma-rays produced from different final state Standard Model particles, annihilation with internal bremsstrahlung, monochromatic lines and box-shaped signals. Our results represent the most stringent constraints to the annihilation cross-section or decay lifetime obtained from observations of satellite galaxies, for masses above few hundred GeV. In particular, our strongest limit (95% confidence level) corresponds to a ?500 GeV dark matter particle annihilating into ?{sup +}?{sup ?}, and is of order (?{sub ann}v)? 1.2נ10{sup ?24}cm{sup 3}s{sup ?1} a factor ? 40 above the (?{sub ann}v)? thermal value.

  14. GO, an exec for running the programs: CELL, COLLIDER, MAGIC, PATRICIA, PETROS, TRANSPORT, and TURTLE

    SciTech Connect (OSTI)

    Shoaee, H.

    1982-05-01

    An exec has been written and placed on the PEP group's public disk to facilitate the use of several PEP related computer programs available on VM. The exec's program list currently includes: CELL, COLLIDER, MAGIC, PATRICIA, PETROS, TRANSPORT, and TURTLE. In addition, provisions have been made to allow addition of new programs to this list as they become available. The GO exec is directly callable from inside the Wylbur editor (in fact, currently this is the only way to use the GO exec.). It provides the option of running any of the above programs in either interactive or batch mode. In the batch mode, the GO exec sends the data in the Wylbur active file along with the information required to run the job to the batch monitor (BMON, a virtual machine that schedules and controls execution of batch jobs). This enables the user to proceed with other VM activities at his/her terminal while the job executes, thus making it of particular interest to the users with jobs requiring much CPU time to execute and/or those wishing to run multiple jobs independently. In the interactive mode, useful for small jobs requiring less CPU time, the job is executed by the user's own Virtual Machine using the data in the active file as input. At the termination of an interactive job, the GO exec facilitates examination of the output by placing it in the Wylbur active file.

  15. GO, an exec for running the programs: CELL, COLLIDER, MAGIC, PATRICIA, PETROS, TRANSPORT and TURTLE

    SciTech Connect (OSTI)

    Shoaee, H.

    1982-05-01

    An exec has been written and placed on the PEP group's public disk (PUBRL 192) to facilitate the use of several PEP related computer programs available on VM. The exec's program list currently includes: CELL, COLLIDER, MAGIC, PATRICIA, PETROS, TRANSPORT, and TURTLE. In addition, provisions have been made to allow addition of new programs to this list as they become available. The GO exec is directly callable from inside the Wylbur editor (in fact, currently this is the only way to use the GO exec.) It provides the option of running any of the above programs in either interactive or batch mode. In the batch mode, the GO exec sends the data in the Wylbur active file along with the information required to run the job to the batch monitor (BMON, a virtual machine that schedules and controls execution of batch jobs). This enables the user to proceed with other VM activities at his/her terminal while the job executes, thus making it of particular interest to the users with jobs requiring much CPU time to execute and/or those wishing to run multiple jobs independently. In the interactive mode, useful for small jobs requiring less CPU time, the job is executed by the user's own Virtual Machine using the data in the active file as input. At the termination of an interactive job, the GO exec facilitates examination of the output by placing it in the Wylbur active file.

  16. Optimized dark matter searches in deep observations of Segue 1 with MAGIC

    SciTech Connect (OSTI)

    Aleksić, J.; Ansoldi, S.; Antonelli, L.A.; Antoranz, P.; Collaboration: The The MAGIC Collaboration; and others

    2014-02-06

    We present the results of stereoscopic observations of the satellite galaxy Segue 1 with the MAGIC Telescopes, carried out between 2011 and 2013. With almost 160 hours of good-quality data, this is the deepest observational campaign on any dwarf galaxy performed so far in the very high energy range of the electromagnetic spectrum. We search this large data sample for signals of dark matter particles in the mass range between 100 GeV and 20 TeV. For this we use the full likelihood analysis method, which provides optimal sensitivity to characteristic gamma-ray spectral features, like those expected from dark matter annihilation or decay. In particular, we focus our search on gamma-rays produced from different final state Standard Model particles, annihilation with internal bremsstrahlung, monochromatic lines and box-shaped signals. Our results represent the most stringent constraints to the annihilation cross-section or decay lifetime obtained from observations of satellite galaxies, for masses above few hundred GeV. In particular, our strongest limit (95% confidence level) corresponds to a ∼500 GeV dark matter particle annihilating into τ{sup +}τ{sup −}, and is of order <σ{sub ann}v>≃ 1.2×10{sup −24} cm{sup 3} s{sup −1} — a factor ∼40 above the <σ{sub ann}v>≃ thermal value.

  17. Mira, an angle shot | Argonne Leadership Computing Facility

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

    an angle shot Download original image « Back to galleryItem 1 of 9Next

  18. Emergent spin electromagnetism induced by magnetization textures in the presence of spin-orbit interaction (invited)

    SciTech Connect (OSTI)

    Tatara, Gen; Nakabayashi, Noriyuki

    2014-05-07

    Emergent electromagnetic field which couples to electron's spin in ferromagnetic metals is theoretically studied. Rashba spin-orbit interaction induces spin electromagnetic field which is in the linear order in gradient of magnetization texture. The Rashba-induced effective electric and magnetic fields satisfy in the absence of spin relaxation the Maxwell's equations as in the charge-based electromagnetism. When spin relaxation is taken into account besides spin dynamics, a monopole current emerges generating spin motive force via the Faraday's induction law. The monopole is expected to play an important role in spin-charge conversion and in the integration of spintronics into electronics.

  19. Spin-polaron theory of high-{Tc} superconductivity: I, spin polarons...

    Office of Scientific and Technical Information (OSTI)

    Subject: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; HIGH-TC SUPERCONDUCTORS; PAIRING ENERGY; POLARONS; SPIN; SPIN FLIP; COPPER OXIDES 665411; BASIC ...

  20. Solar concentrator with restricted exit angles

    DOE Patents [OSTI]

    Rabl, Arnulf; Winston, Roland

    1978-12-19

    A device is provided for the collection and concentration of radiant energy and includes at least one reflective side wall. The wall directs incident radiant energy to the exit aperture thereof or onto the surface of energy absorber positioned at the exit aperture so that the angle of incidence of radiant energy at the exit aperture or on the surface of the energy absorber is restricted to desired values.

  1. Multi-Angle Snowflake Camera Instrument Handbook

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

    8 Multi-Angle Snowflake Camera Instrument Handbook July 2016 M Stuefer J Bailey DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe

  2. Small Angle X-Ray Scattering Detector

    DOE Patents [OSTI]

    Hessler, Jan P.

    2004-06-15

    A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., q.sub.max /q.sub.min.congruent.100.

  3. Angle sensitive single photon avalanche diode

    SciTech Connect (OSTI)

    Lee, Changhyuk Johnson, Ben Molnar, Alyosha

    2015-06-08

    An ideal light sensor would provide exact information on intensity, timing, location, and angle of incoming photons. Single photon avalanche diodes (SPADs) provide such desired high (single photon) sensitivity with precise time information and can be implemented at a pixel-scale to form an array to extract spatial information. Furthermore, recent work has demonstrated photodiode-based structures (combined with micro-lenses or diffraction gratings) that are capable of encoding both spatial and angular information of incident light. In this letter, we describe the implementation of such a grating structure on SPADs to realize a pixel-scale angle-sensitive single photon avalanche diode (A-SPAD) built in a standard CMOS process. While the underlying SPAD structure provides high sensitivity, the time information of the two layers of diffraction gratings above offers angle-sensitivity. Such a unique combination of SPAD and diffraction gratings expands the sensing dimensions to pave a path towards lens-less 3-D imaging and light-field time-of-flight imaging.

  4. Classically spinning and isospinning solitons

    SciTech Connect (OSTI)

    Battye, Richard A.; Haberichter, Mareike

    2012-09-26

    We investigate classically spinning topological solitons in (2+1)- and (3+1)-dimensional models; more explicitely spinning sigma model solitons in 2+1 dimensions and Skyrme solitons in 2+1 and 3+1 dimensions. For example, such types of solitons can be used to describe quasiparticle excitations in ferromagnetic quantum Hall systems or to model spin and isospin states of nuclei. The standard way to obtain solitons with quantised spin and isospin is the semiclassical quantization procedure: One parametrizes the zero-mode space - the space of energy-degenerate soliton configurations generated from a single soliton by spatial translations and rotations in space and isospace - by collective coordinates which are then taken to be time-dependent. This gives rise to additional dynamical terms in the Hamiltonian which can then be quantized following semiclassical quantization rules. A simplification which is often made in the literature is to apply a simple adiabatic approximation to the (iso)rotational zero modes of the soliton by assuming that the soliton's shape is rotational frequency independent. Our numerical results on classically spinning arbitrarily deforming soliton solutions clearly show that soliton deformation cannot be ignored.

  5. Highly selective detection of individual nuclear spins with rotary...

    Office of Scientific and Technical Information (OSTI)

    of individual nuclear spins with rotary echo on an electron spin probe Citation Details In-Document Search Title: Highly selective detection of individual nuclear spins with ...

  6. J lich Neutron Spin Echo Instrument Inaugurated (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    J lich Neutron Spin Echo Instrument Inaugurated Citation Details In-Document Search Title: J lich Neutron Spin Echo Instrument Inaugurated The neutron spin echo (NSE) spectrometer ...

  7. Highlights and Perspectives of the JLab Spin Physics Program...

    Office of Scientific and Technical Information (OSTI)

    Highlights and Perspectives of the JLab Spin Physics Program Citation Details In-Document Search Title: Highlights and Perspectives of the JLab Spin Physics Program Nucleon spin ...

  8. Induction-detection electron spin resonance with spin sensitivity of a few tens of spins

    SciTech Connect (OSTI)

    Artzi, Yaron; Twig, Ygal; Blank, Aharon

    2015-02-23

    Electron spin resonance (ESR) is a spectroscopic method that addresses electrons in paramagnetic materials directly through their spin properties. ESR has many applications, ranging from semiconductor characterization to structural biology and even quantum computing. Although it is very powerful and informative, ESR traditionally suffers from low sensitivity, requiring many millions of spins to get a measureable signal with commercial systems using the Faraday induction-detection principle. In view of this disadvantage, significant efforts were made recently to develop alternative detection schemes based, for example, on force, optical, or electrical detection of spins, all of which can reach single electron spin sensitivity. This sensitivity, however, comes at the price of limited applicability and usefulness with regard to real scientific and technological issues facing modern ESR which are currently dealt with conventional induction-detection ESR on a daily basis. Here, we present the most sensitive experimental induction-detection ESR setup and results ever recorded that can detect the signal from just a few tens of spins. They were achieved thanks to the development of an ultra-miniature micrometer-sized microwave resonator that was operated at ∼34 GHz at cryogenic temperatures in conjunction with a unique cryogenically cooled low noise amplifier. The test sample used was isotopically enriched phosphorus-doped silicon, which is of significant relevance to spin-based quantum computing. The sensitivity was experimentally verified with the aid of a unique high-resolution ESR imaging approach. These results represent a paradigm shift with respect to the capabilities and possible applications of induction-detection-based ESR spectroscopy and imaging.

  9. Pair Creation at Large Inherent Angles

    SciTech Connect (OSTI)

    Chen, P.; Tauchi, T.; Schroeder, D.V.; /SLAC

    2007-04-25

    In the next-generation linear colliders, the low-energy e{sup +}e{sup -} pairs created during the collision of high-energy e{sup +}e{sup -} beams would cause potential deleterious background problems to the detectors. At low collider energies, the pairs are made essentially by the incoherent process, where the pair is created by the interaction of beamstrahlung photons on the individual particles in the oncoming beam. This problem was first identified by Zolotarev, et al[1]. At energies where the beamstrahlung parameter {Upsilon} lies approximately in the range 0.6 {approx}< {Upsilon} {approx}< 100, pair creation from the beamstrahlung photons is dominated by a coherent process, first noted by Chen[2]. The seriousness of this pair creation problem lies in the transverse momenta that the pair particles carry when leaving the interaction point (IP) with large angles. One source of transverse momentum is from the kick by the field of the oncoming beam which results in an outcoming angle {theta} {proportional_to} 1/{radical}x, where x is the fractional energy of the particle relative to the initial beam particle energy[2,3]. As was shown in Ref. 131, there in fact exists an energy threshold for the coherent pairs, where x{sub th} {approx}> 1/2{Upsilon}. Thus within a tolerable exiting angle, there exists an upper limit for {Upsilon} where all coherent pairs would leave the detector through the exhaust port[4]. A somewhat different analysis has been done by Schroeder[5]. In the next generation of linear colliders, as it occurs, the coherent pairs can be exponentially suppressed[2] by properly choosing the {Upsilon}({approx}< 0.6). When this is achieved, the incoherent pairs becomes dominant. Since the central issue is the transverse momentum for particles with large angles, we notice that there is another source for it. Namely, when the pair particles are created at low energies, the intrinsic angles of these pairs when produced may already be large. This issue was

  10. Clouds, Precipitation, and Marine Boundary Layer Structure during the MAGIC Field Campaign

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

    Zhou, Xiaoli; Kollias, Pavlos; Lewis, Ernie R.

    2015-03-01

    The recent ship-based MAGIC (Marine ARM GCSS Pacific Cross-Section Intercomparison (GPCI) Investigation of Clouds) field campaign with the marine-capable Second ARM Mobile Facility (AMF2) deployed on the Horizon Lines cargo container M/V Spirit provided nearly 200 days of intraseasonal high-resolution observations of clouds, precipitation, and marine boundary layer (MBL) structure on multiple legs between Los Angeles, California, and Honolulu, Hawaii. During the deployment, MBL clouds exhibited a much higher frequency of occurrence than other cloud types and occurred more often in the warm season than in the cold season. MBL clouds demonstrated a propensity to produce precipitation, which often evaporatedmore » before reaching the ocean surface. The formation of stratocumulus is strongly correlated to a shallow MBL with a strong inversion and a weak transition, while cumulus formation is associated with a much weaker inversion and stronger transition. The estimated inversion strength is shown to depend seasonally on the potential temperature at 700 hPa. The location of the commencement of systematic MBL decoupling always occurred eastward of the locations of cloud breakup, and the systematic decoupling showed a strong moisture stratification. The entrainment of the dry warm air above the inversion appears to be the dominant factor triggering the systematic decoupling, while surface latent heat flux, precipitation, and diurnal circulation did not play major roles. MBL clouds broke up over a short spatial region due to the changes in the synoptic conditions, implying that in real atmospheric conditions the MBL clouds do not have enough time to evolve as in the idealized models. (auth)« less

  11. Clouds, Precipitation, and Marine Boundary Layer Structure during the MAGIC Field Campaign

    SciTech Connect (OSTI)

    Zhou, Xiaoli; Kollias, Pavlos; Lewis, Ernie R.

    2015-03-01

    The recent ship-based MAGIC (Marine ARM GCSS Pacific Cross-Section Intercomparison (GPCI) Investigation of Clouds) field campaign with the marine-capable Second ARM Mobile Facility (AMF2) deployed on the Horizon Lines cargo container M/V Spirit provided nearly 200 days of intraseasonal high-resolution observations of clouds, precipitation, and marine boundary layer (MBL) structure on multiple legs between Los Angeles, California, and Honolulu, Hawaii. During the deployment, MBL clouds exhibited a much higher frequency of occurrence than other cloud types and occurred more often in the warm season than in the cold season. MBL clouds demonstrated a propensity to produce precipitation, which often evaporated before reaching the ocean surface. The formation of stratocumulus is strongly correlated to a shallow MBL with a strong inversion and a weak transition, while cumulus formation is associated with a much weaker inversion and stronger transition. The estimated inversion strength is shown to depend seasonally on the potential temperature at 700 hPa. The location of the commencement of systematic MBL decoupling always occurred eastward of the locations of cloud breakup, and the systematic decoupling showed a strong moisture stratification. The entrainment of the dry warm air above the inversion appears to be the dominant factor triggering the systematic decoupling, while surface latent heat flux, precipitation, and diurnal circulation did not play major roles. MBL clouds broke up over a short spatial region due to the changes in the synoptic conditions, implying that in real atmospheric conditions the MBL clouds do not have enough time to evolve as in the idealized models. (auth)

  12. Dependence of inverse-spin Hall effect and spin-rectified voltage on tantalum thickness in Ta/CoFeB bilayer structure

    SciTech Connect (OSTI)

    Kim, Sang-Il; Seo, Min-Su; Park, Seung-Young; Kim, Dong-Jun; Park, Byong-Guk

    2015-01-19

    Ta-layer thickness (t{sub Ta}) dependence of the measured DC voltage V from the inverse-spin Hall effect (ISHE) in Ta/CoFeB bilayer structure is experimentally investigated using the ferromagnetic resonance in the TE{sub 011} resonant cavity. The ISHE signals excluding the spin-rectified effect (SRE) were separated from the fitted curve of V against t{sub Ta}. For t{sub Ta} ≈ λ{sub Ta} (Ta-spin diffusion length = 2.7 nm), the deviation in ISHE voltage V{sub ISH} between the experimental and theoretical values is significantly increased because of the large SRE contribution, which also results in a large deviation in the spin Hall angle θ{sub SH} (from 10% to 40%). However, when t{sub Ta} ≫ λ{sub Ta}, the V{sub ISH} values are consistent with theoretical values because the SRE terms become negligible, which subsequently improves the accuracy of the obtained θ{sub SH} within 4% deviation. The results will provide an outline for an accurate estimation of the θ{sub SH} for materials with small λ value, which would be useful for utilizing the spin Hall effect in a 3-terminal spintronic devices in which magnetization can be controlled by in-plane current.

  13. Antiferromagnetic Spin Wave Field-Effect Transistor

    Office of Scientific and Technical Information (OSTI)

    ... Assume that the spin wave is generated at one end of the chain by an oscillating magnetic field along the y-direction at 1.4 THz. tte spin wave is subsequently modulated by a 20 ...

  14. Magnetic interactions in strongly correlated systems: Spin and orbital contributions

    SciTech Connect (OSTI)

    Secchi, A.; Lichtenstein, A.I.; Katsnelson, M.I.

    2015-09-15

    We present a technique to map an electronic model with local interactions (a generalized multi-orbital Hubbard model) onto an effective model of interacting classical spins, by requiring that the thermodynamic potentials associated to spin rotations in the two systems are equivalent up to second order in the rotation angles, when the electronic system is in a symmetry-broken phase. This allows to determine the parameters of relativistic and non-relativistic magnetic interactions in the effective spin model in terms of equilibrium Green’s functions of the electronic model. The Hamiltonian of the electronic system includes, in addition to the non-relativistic part, relativistic single-particle terms such as the Zeeman coupling to an external magnetic field, spin–orbit coupling, and arbitrary magnetic anisotropies; the orbital degrees of freedom of the electrons are explicitly taken into account. We determine the complete relativistic exchange tensors, accounting for anisotropic exchange, Dzyaloshinskii–Moriya interactions, as well as additional non-diagonal symmetric terms (which may include dipole–dipole interaction). The expressions of all these magnetic interactions are determined in a unified framework, including previously disregarded features such as the vertices of two-particle Green’s functions and non-local self-energies. We do not assume any smallness in spin–orbit coupling, so our treatment is in this sense exact. Finally, we show how to distinguish and address separately the spin, orbital and spin–orbital contributions to magnetism, providing expressions that can be computed within a tight-binding Dynamical Mean Field Theory.

  15. Electron Spin Dynamics in Semiconductor Quantum Dots

    SciTech Connect (OSTI)

    Marie, X.; Belhadj, T.; Urbaszek, B.; Amand, T.; Krebs, O.; Lemaitre, A.; Voisin, P.

    2011-07-15

    An electron spin confined to a semiconductor quantum dot is not subject to the classical spin relaxation mechanisms known for free carriers but it strongly interacts with the nuclear spin system via the hyperfine interaction. We show in time resolved photoluminescence spectroscopy experiments on ensembles of self assembled InAs quantum dots in GaAs that this interaction leads to strong electron spin dephasing.

  16. Infrared spectroscopic investigation of nuclear spin conversion...

    Office of Scientific and Technical Information (OSTI)

    relaxation processes mediated by phonons to the temperature dependence of these ... INFRARED SPECTRA; METHANE; MOLECULES; PHONONS; RELAXATION; SOLIDS; SPIN; TEMPERATURE ...

  17. Spin-forming Project Report

    SciTech Connect (OSTI)

    Switzner, Nathan; Henry, Dick

    2009-03-20

    In a second development order, spin-forming equipment was again evaluated using the test shape, a hemispherical shell. In this second development order, pure vanadium and alloy titanium (Ti-6Al-4V) were spin-formed, as well as additional copper and 21-6-9 stainless. In the first development order the following materials had been spin-formed: copper (alloy C11000 ETP), 6061 aluminum, 304L stainless steel, 21-6-9 stainless steel, and tantalum-2.5% tungsten. Significant challenges included properly adjusting the rotations-per-minute (RPM), cracking at un-beveled edges and laser marks, redressing of notches, surface cracking, non-uniform temperature evolution in the titanium, and cracking of the tailstock. Lessons learned were that 300 RPM worked better than 600 RPM for most materials (at the feed rate of 800 mm/min); beveling the edges to lower the stress reduces edge cracking; notches, laser marks, or edge defects in the preform doom the process to cracking and failure; coolant is required for vanadium spin-forming; increasing the number of passes to nine or more eliminates surface cracking for vanadium; titanium develops a hot zone in front of the rollers; and the tailstock should be redesigned to eliminate the cylindrical stress concentrator in the center.

  18. Spinning Reserve From Responsive Loads

    SciTech Connect (OSTI)

    Kirby, B.J.

    2003-04-08

    Responsive load is the most underutilized reliability resource available to the power system today. It is currently not used at all to provide spinning reserve. Historically there were good reasons for this, but recent technological advances in communications and controls have provided new capabilities and eliminated many of the old obstacles. North American Electric Reliability Council (NERC), Federal Energy Regulatory Commission (FERC), Northeast Power Coordinating Council (NPCC), New York State Reliability Council (NYSRC), and New York Independent System Operator (NYISO) rules are beginning to recognize these changes and are starting to encourage responsive load provision of reliability services. The Carrier ComfortChoice responsive thermostats provide an example of these technological advances. This is a technology aimed at reducing summer peak demand through central control of residential and small commercial air-conditioning loads. It is being utilized by Long Island Power Authority (LIPA), Consolidated Edison (ConEd), Southern California Edison (SCE), and San Diego Gas and Electric (SDG&E). The technology is capable of delivering even greater response in the faster spinning reserve time frame (while still providing peak reduction). Analysis of demand reduction testing results from LIPA during the summer of 2002 provides evidence to back up this claim. It also demonstrates that loads are different from generators and that the conventional wisdom, which advocates for starting with large loads as better ancillary service providers, is flawed. The tempting approach of incrementally adapting ancillary service requirements, which were established when generators were the only available resources, will not work. While it is easier for most generators to provide replacement power and non-spinning reserve (the slower response services) than it is to supply spinning reserve (the fastest service), the opposite is true for many loads. Also, there is more financial

  19. Enhanced spin Seebeck effect signal due to spin-momentum locked topological

    Office of Scientific and Technical Information (OSTI)

    surface states (Journal Article) | SciTech Connect Journal Article: Enhanced spin Seebeck effect signal due to spin-momentum locked topological surface states Citation Details In-Document Search Title: Enhanced spin Seebeck effect signal due to spin-momentum locked topological surface states Spin-momentum locking in protected surface states enables efficient electrical detection of magnon decay at a magnetic-insulator/topological-insulator heterojunction. Here we demonstrate this property

  20. Spin in the Neutron | Jefferson Lab

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

    in the Neutron Spin in the Neutron NEWPORT NEWS, Va. - Puzzling out the source of proton and neutron spin is part of the ongoing experimental effort at Jefferson Lab to understand their structure and the structure of the nucleus of the atom. Since the proton spin crisis, scientists have learned that a proton's spin comes not only from the spin of its quarks, but also from how the quarks move inside the proton, the quarks' so-called orbital angular momentum. Orbital angular momentum can be simply

  1. Analysis of the spin Hall effect in CuIr alloys: Combined approach of density functional theory and Hartree-Fock approximation

    SciTech Connect (OSTI)

    Xu, Zhuo Gu, Bo; Mori, Michiyasu; Maekawa, Sadamichi; Ziman, Timothy

    2015-05-07

    We analyze the spin Hall effect in CuIr alloys in theory by the combined approach of the density functional theory (DFT) and Hartree-Fock (HF) approximation. The spin Hall angle (SHA) is obtained to be negative without the local correlation effects. After including the local correlation effects of the 5d orbitals of Ir impurities, the SHA becomes positive with realistic correlation parameters and consistent with experiment [Niimi et al., Phys. Rev. Lett. 106, 126601 (2011)]. Moreover, our analysis shows that the DFT + HF approach is a convenient and general method to study the influence of local correlation effects on the spin Hall effect.

  2. Geometric spin manipulation in semiconductor quantum dots

    SciTech Connect (OSTI)

    Prabhakar, Sanjay Melnik, Roderick; Inomata, Akira

    2014-04-07

    We propose a method to flip the spin completely by an adiabatic transport of quantum dots. We show that it is possible to flip the spin by inducing a geometric phase on the spin state of a quantum dot. We estimate the geometric spin flip time (approximately 2 ps) which turned out to be much shorter than the experimentally reported decoherence time (approximately 100 ns) that would provide an alternative means of fliping the spin before reaching decoherence. It is important that both the Rashba coupling and the Dresselhaus coupling are present for inducing a phase necessary for spin flip. If one of them is absent, the induced phase is trivial and irrelevant for spin-flip.

  3. Realization of tunable spin-dependent splitting in intrinsic photonic spin Hall effect

    SciTech Connect (OSTI)

    Ling, Xiaohui; Yi, Xunong; Zhou, Xinxing; Liu, Yachao; Shu, Weixing; Wen, Shuangchun; Luo, Hailu

    2014-10-13

    We report the realization of tunable spin-dependent splitting in intrinsic photonic spin Hall effect. By breaking the rotational symmetry of a cylindrical vector beam, the intrinsic vortex phases that the two spin components of the vector beam carries, which is similar to the geometric Pancharatnam-Berry phase, are no longer continuous in the azimuthal direction, and leads to observation of spin accumulation at the opposite edge of the beam. Due to the inherent nature of the phase and independency of light-matter interaction, the observed photonic spin Hall effect is intrinsic. Modulating the topological charge of the vector beam, the spin-dependent splitting can be enhanced and the direction of spin accumulation is switchable. Our findings may provide a possible route for generation and manipulation of spin-polarized photons, and enables spin-based photonics applications.

  4. Spontaneous Coherence and Spin Texture

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

    Spontaneous Coherence and Spin Texture - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management

  5. Demand Response Spinning Reserve Demonstration

    SciTech Connect (OSTI)

    Eto, Joseph H.; Nelson-Hoffman, Janine; Torres, Carlos; Hirth,Scott; Yinger, Bob; Kueck, John; Kirby, Brendan; Bernier, Clark; Wright,Roger; Barat, A.; Watson, David S.

    2007-05-01

    The Demand Response Spinning Reserve project is a pioneeringdemonstration of how existing utility load-management assets can providean important electricity system reliability resource known as spinningreserve. Using aggregated demand-side resources to provide spinningreserve will give grid operators at the California Independent SystemOperator (CAISO) and Southern California Edison (SCE) a powerful, newtool to improve system reliability, prevent rolling blackouts, and lowersystem operating costs.

  6. Spin-dependent Seebeck effects in a graphene nanoribbon coupled to two square lattice ferromagnetic leads

    SciTech Connect (OSTI)

    Zhou, Benhu Zeng, Yangsu; Zhou, Benliang; Zhou, Guanghui; Ouyang, Tao

    2015-03-14

    We theoretically investigate spin-dependent Seebeck effects for a system consisting of a narrow graphene nanoribbon (GNR) contacted to square lattice ferromagnetic (FM) electrodes with noncollinear magnetic moments. Both zigzag-edge graphene nanoribbons (ZGNRs) and armchair-edge graphene nanoribbons (AGNRs) were considered. Compared with our previous work with two-dimensional honeycomb-lattice FM leads, a more realistic model of two-dimensional square-lattice FM electrodes is adopted here. Using the nonequilibrium Green's function method combining with the tight-binding Hamiltonian, it is demonstrated that both the charge Seebeck coefficient S{sub C} and the spin-dependent Seebeck coefficient S{sub S} strongly depend on the geometrical contact between the GNR and the leads. In our previous work, S{sub C} for a semiconducting 15-AGNR system near the Dirac point is two orders of magnitude larger than that of a metallic 17-AGNR system. However, S{sub C} is the same order of magnitude for both metallic 17-AGNR and semiconducting 15-AGNR systems in the present paper because of the lack of a transmission energy gap for the 15-AGNR system. Furthermore, the spin-dependent Seebeck coefficient S{sub S} for the systems with 20-ZGNR, 17-AGNR, and 15-AGNR is of the same order of magnitude and its maximum absolute value can reach 8 μV/K. The spin-dependent Seebeck effects are not very pronounced because the transmission coefficient weakly depends on spin orientation. Moreover, the spin-dependent Seebeck coefficient is further suppressed with increasing angle between the relative alignments of magnetization directions of the two leads. Additionally, the spin-dependent Seebeck coefficient can be strongly suppressed for larger disorder strength. The results obtained here may provide valuable theoretical guidance in the experimental design of heat spintronic devices.

  7. Ab initio non-relativistic spin dynamics

    SciTech Connect (OSTI)

    Ding, Feizhi; Goings, Joshua J.; Li, Xiaosong; Frisch, Michael J.

    2014-12-07

    Many magnetic materials do not conform to the (anti-)ferromagnetic paradigm where all electronic spins are aligned to a global magnetization axis. Unfortunately, most electronic structure methods cannot describe such materials with noncollinear electron spin on account of formally requiring spin alignment. To overcome this limitation, it is necessary to generalize electronic structure methods and allow each electron spin to rotate freely. Here, we report the development of an ab initio time-dependent non-relativistic two-component spinor (TDN2C), which is a generalization of the time-dependent Hartree-Fock equations. Propagating the TDN2C equations in the time domain allows for the first-principles description of spin dynamics. A numerical tool based on the Hirshfeld partitioning scheme is developed to analyze the time-dependent spin magnetization. In this work, we also introduce the coupling between electron spin and a homogenous magnetic field into the TDN2C framework to simulate the response of the electronic spin degrees of freedom to an external magnetic field. This is illustrated for several model systems, including the spin-frustrated Li{sub 3} molecule. Exact agreement is found between numerical and analytic results for Larmor precession of hydrogen and lithium atoms. The TDN2C method paves the way for the ab initio description of molecular spin transport and spintronics in the time domain.

  8. A two dimensional silicon detectors array for quality assurance in stereotactic radiotherapy: MagicPlate-512

    SciTech Connect (OSTI)

    Aldosari, A. H.; Petasecca, M. Espinoza, A.; Newall, M.; Fuduli, I.; Porumb, C.; Alshaikh, S.; Alrowaili, Z. A.; Weaver, M.; Metcalfe, P.; Lerch, M. L. F.; Rosenfeld, A. B.; Carolan, M.; Perevertaylo, V.

    2014-09-15

    Purpose: Silicon diode arrays are commonly implemented in radiation therapy quality assurance applications as they have a number of advantages including: real time operation (compared to the film) and high spatial resolution, large dynamic range and small size (compared to ionizing chambers). Most diode arrays have detector pitch that is too coarse for routine use in small field applications. The goal of this work is to characterize the two-dimensional monolithic silicon diode array named “MagicPlate-512” (MP512) designed for QA in stereotactic body radiation therapy (SBRT) and stereotactic radio surgery (SRS). Methods: MP512 is a silicon monolithic detector manufactured on ap-type substrate. An array contains of 512 pixels with size 0.5 × 0.5 mm{sup 2} and pitch 2 mm with an overall dimension of 52 × 52 mm{sup 2}. The MP512 monolithic detector is wire bonded on a printed circuit board 0.5 mm thick and covered by a thin layer of raisin to preserve the silicon detector from moisture and chemical contamination and to protect the bonding wires. Characterization of the silicon monolithic diode array response was performed, and included pixels response uniformity, dose linearity, percent depth dose, output factor, and beam profiling for beam sizes relevant to SBRT and SRS and depth dose response in comparison with ionization chamber. Results: MP512 shows a good dose linearity (R{sup 2} = 0.998) and repeatability within 0.2%. The measured depth dose response for field size of 10 × 10 cm{sup 2} agreed to within 1.3%, when compared to a CC13 ionization chamber for depths in PMMA up to 30 cm. The output factor of a 6 MV Varian 2100EX medical linac beam measured by MP512 at the isocenter agrees to within 2% when compared to PTW diamond, Scanditronix point EDD-2 diode and MOSkin detectors for field sizes down to 1 × 1 cm{sup 2}. An over response of 4% was observed for square beam size smaller than 1 cm when compared to EBT3 films, while the beam profiles (FWHM) of MP

  9. An electron energy loss spectrometer designed for studies of electronic energy losses and spin waves in the large momentum regime

    SciTech Connect (OSTI)

    Ibach, H.; Rajeswari, J.; Schneider, C. M.

    2011-12-15

    Based on 143 deg. electrostatic deflectors we have realized a new spectrometer for electron energy loss spectroscopy which is particularly suitable for studies on surface spin waves and other low energy electronic energy losses. Contrary to previous designs high resolution is maintained even for diffuse inelastic scattering due to a specific management of the angular aberrations in combination with an angle aperture. The performance of the instrument is demonstrated with high resolution energy loss spectra of surface spin waves on a cobalt film deposited on the Cu(100) surface.

  10. {gamma} spectroscopy around doubly magic {sup 48}Ca by heavy-ion transfer reactions

    SciTech Connect (OSTI)

    Leoni, Silvia

    2012-10-20

    {gamma} spectroscopy of neutron-rich nuclei around {sup 48}Ca is performed by the heavy-ion transfer reaction {sup 48}Ca on {sup 64}Ni at 282 MeV, with the PRISMA-CLARA setup at Legnaro Laboratory. Angular distributions, polarizations and lifetimes analysis probe spin and parities of several excited states, shading lights on their configuration. In the one neutron transfer channels, {sup 49}Ca and {sup 47}Ca, states arising by coupling a single particle to the 3{sup -} phonon of {sup 48}Ca are observed, showing the robustness of nuclear collectivity in rather light systems. The work demonstrates the feasibility of complete in-beam {gamma}-spectroscopy with heavy-ion transfer reactions and provides a method that can be further exploited in the future with heavy targets and radioactive beams.

  11. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Print Inherently strange crystalline materials called 3D topological insulators (TIs) are all the rage in materials science. This new phase of condensed matter is an insulator in the bulk, yet behaves like a metal on its surface, even at room temperature. The electrons that flow swiftly across the surfaces of TIs are "spin polarized", meaning the electron's spin is locked to its momentum, perpendicular to the direction of travel.

  12. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Print Inherently strange crystalline materials called 3D topological insulators (TIs) are all the rage in materials science. This new phase of condensed matter is an insulator in the bulk, yet behaves like a metal on its surface, even at room temperature. The electrons that flow swiftly across the surfaces of TIs are "spin polarized", meaning the electron's spin is locked to its momentum, perpendicular to the direction of travel.

  13. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Print Inherently strange crystalline materials called 3D topological insulators (TIs) are all the rage in materials science. This new phase of condensed matter is an insulator in the bulk, yet behaves like a metal on its surface, even at room temperature. The electrons that flow swiftly across the surfaces of TIs are "spin polarized", meaning the electron's spin is locked to its momentum, perpendicular to the direction of travel.

  14. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Print Inherently strange crystalline materials called 3D topological insulators (TIs) are all the rage in materials science. This new phase of condensed matter is an insulator in the bulk, yet behaves like a metal on its surface, even at room temperature. The electrons that flow swiftly across the surfaces of TIs are "spin polarized", meaning the electron's spin is locked to its momentum, perpendicular to the direction of travel.

  15. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Print Inherently strange crystalline materials called 3D topological insulators (TIs) are all the rage in materials science. This new phase of condensed matter is an insulator in the bulk, yet behaves like a metal on its surface, even at room temperature. The electrons that flow swiftly across the surfaces of TIs are "spin polarized", meaning the electron's spin is locked to its momentum, perpendicular to the direction of travel.

  16. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Flipping Photoelectron Spins in Topological Insulators Print Tuesday, 23 April 2013 10:00 Inherently strange crystalline materials called 3D topological insulators (TIs) are all the rage in materials science. This new phase of condensed matter is an insulator in the bulk, yet behaves like a metal on its surface, even at room temperature. The electrons that flow swiftly across the surfaces of TIs are "spin polarized", meaning the

  17. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Print Inherently strange crystalline materials called 3D topological insulators (TIs) are all the rage in materials science. This new phase of condensed matter is an insulator in the bulk, yet behaves like a metal on its surface, even at room temperature. The electrons that flow swiftly across the surfaces of TIs are "spin polarized", meaning the electron's spin is locked to its momentum, perpendicular to the direction of travel.

  18. Long-lived nanosecond spin relaxation and spin coherence of electrons...

    Office of Scientific and Technical Information (OSTI)

    In contrast with conventional III-V or II-VI semiconductors, spin relaxation accelerates rapidly in small transverse magnetic fields. Supported by a model of coupled spin-valley ...

  19. Spin-pump-induced spin transport in a thermally evaporated pentacene film

    SciTech Connect (OSTI)

    Tani, Yasuo; Shikoh, Eiji; Teki, Yoshio

    2015-12-14

    We report the spin-pump-induced spin transport properties of a pentacene film prepared by thermal evaporation. In a palladium(Pd)/pentacene/Ni{sub 80}Fe{sub 20} tri-layer sample, a pure spin-current is generated in the pentacene layer by the spin-pumping of Ni{sub 80}Fe{sub 20}, which is independent of the conductance mismatch problem in spin injection. The spin current is absorbed into the Pd layer, converted into a charge current with the inverse spin-Hall effect in Pd, and detected as an electromotive force. This is clear evidence for the pure spin current at room temperature in pentacene films prepared by thermal evaporation.

  20. Enhanced spin Seebeck effect signal due to spin-momentum locked...

    Office of Scientific and Technical Information (OSTI)

    ... pure spin current generation by heat is already ... proportional to the heater power, DTpP I2Rheater, where I ... C. L. Intrinsic spin-dependent thermal transport. Phys. Rev. ...

  1. Flipping Photoelectron Spins in Topological Insulators

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

    Spintronics The ability to shine polarized light on a topological insulator (TI) and excite spin-polarization-tailored electrons has great potential for the field of spintronics - ...

  2. Top Quark Spin Correlations at the Tevatron

    SciTech Connect (OSTI)

    Head, Tim; /Manchester U.

    2010-07-01

    Recent measurements of the correlation between the spin of the top and the spin of the anti-top quark produced in proton anti-proton scattering at a center of mass energy of {radical}s = 1.96 Tev by the CDF and D0 collaborations are discussed. using up to 4.3 fb{sup -1} of data taken with the CDF and D0 detectors the spin correlation parameter C, the degree to which the spins are correlated, is measured in dileptonic and semileptonic final states. The measurements are found to be in agreement with Standard Model predictions.

  3. Electronic Spin Transition in Nanosize Stoichiometric Lithium...

    Office of Scientific and Technical Information (OSTI)

    Title: Electronic Spin Transition in Nanosize Stoichiometric Lithium Cobalt Oxide Authors: ... Language: English Subject: energy storage (including batteries and capacitors), defects, ...

  4. Flipping Photoelectron Spins in Topological Insulators

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

    is an insulator, but electrons (grey spheres) move swiftly on the surface as if through a metal. They are spin polarized, however, with their momenta (directional ribbons) and...

  5. Flipping Photoelectron Spins in Topological Insulators

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

    The interior bulk of a topological insulator is an insulator, but electrons (grey spheres) move swiftly on the surface as if through a metal. They are spin polarized,...

  6. Spin caloritronics in graphene with Mn

    SciTech Connect (OSTI)

    Torres, Alberto Lima, Matheus P. Fazzio, A.; Silva, Antnio J. R. da

    2014-02-17

    We show that graphene with Mn adatoms trapped at single vacancies features spin-dependent Seebeck effect, thus enabling the use of this material for spin caloritronics. A gate potential can be used to tune its thermoelectric properties in a way it presents either a total spin polarized current, flowing in one given direction, or currents for both spins flowing in opposite directions without net charge transport. Moreover, we show that the thermal magnetoresistance can be tuned between ?100% and +100% by varying a gate potential.

  7. Spin transport in tilted electron vortex beams

    SciTech Connect (OSTI)

    Basu, Banasri; Chowdhury, Debashree

    2014-12-10

    In this paper we have enlightened the spin related issues of tilted Electron vortex beams. We have shown that in the skyrmionic model of electron we can have the spin Hall current considering the tilted type of electron vortex beam. We have considered the monopole charge of the tilted vortex as time dependent and through the time variation of the monopole charge we can explain the spin Hall effect of electron vortex beams. Besides, with an external magnetic field we can have a spin filter configuration.

  8. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Print Inherently strange crystalline materials called 3D ... When energetic photons from a synchrotron light source or laser ...

  9. Theory of unidirectional spin heat conveyer

    SciTech Connect (OSTI)

    Adachi, Hiroto Maekawa, Sadamichi

    2015-05-07

    We theoretically investigate the unidirectional spin heat conveyer effect recently reported in the literature that emerges from the Damon-Eshbach spin wave on the surface of a magnetic material. We develop a simple phenomenological theory for heat transfer dynamics in a coupled system of phonons and the Damon-Eshbach spin wave, and demonstrate that there arises a direction-selective heat flow as a result of the competition between an isotropic heat diffusion by phonons and a unidirectional heat drift by the spin wave. The phenomenological approach can account for the asymmetric local temperature distribution observed in the experiment.

  10. Next to leading order spin(1)spin(1) effects in the motion of inspiralling compact binaries

    SciTech Connect (OSTI)

    Porto, Rafael A.; Rothstein, Ira Z.

    2008-08-15

    Using effective field theory techniques we compute the next to leading order Spin(1)Spin(1) terms in the potential of spinning compact objects at third post-Newtonian (PN) order, including subleading self-induced finite size effects. This result represents the last ingredient to complete the relevant spin potentials to 3PN order from which the equations of motion follow via a canonical formalism. As an example we include the precession equation.

  11. Spinning Reserve from Responsive Load

    SciTech Connect (OSTI)

    Kueck, John D; Kirby, Brendan J; Laughner, T; Morris, K

    2009-01-01

    As power system costs rise and capacity is strained demand response can provide a significant system reliability benefit at a potentially attractive cost. The 162 room Music Road Hotel in Pigeon Forge Tennessee agreed to host a spinning reserve test. The Tennessee Valley Authority (TVA) supplied real-time metering and monitoring expertise to record total hotel load during both normal operations and testing. Preliminary testing showed that hotel load can be curtailed by 22% to 37% depending on the outdoor temperature and the time of day. The load drop was very rapid, essentially as fast as the 2 second metering could detect.

  12. Electron energy spectrum and maximum disruption angle under multi...

    Office of Scientific and Technical Information (OSTI)

    Conference: Electron energy spectrum and maximum disruption angle under multi-photon beamstrahlung Citation Details In-Document Search Title: Electron energy spectrum and maximum ...

  13. Electron energy spectrum and maximum disruption angle under multi...

    Office of Scientific and Technical Information (OSTI)

    Electron energy spectrum and maximum disruption angle under multi-photon beamstrahlung Citation Details In-Document Search Title: Electron energy spectrum and maximum disruption ...

  14. Ligand Bridging-Angle-Driven Assembly of Molecular Architectures...

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

    angles of 0, 60, 90, and 120 while incorporating a variety of nonbridging functional groups, and these ligands were used as linkers. These dicarboxylate linkers assemble with...

  15. Angle-Resolved Photoemission Studies of Quantum Materials (Journal...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Angle-Resolved Photoemission Studies of Quantum Materials Citation ... Cond. Mat. Phys. 3, 129, 2012 Research Org: SLAC National ...

  16. 1/2 l angle 100 r angle l brace 100 r brace dislocation loops in a zinc blende structure

    SciTech Connect (OSTI)

    Chu, S.N.G.; Nakahara, S. )

    1990-01-29

    We report, for the first time, the identification of extrinsic dislocation loops lying on the {l brace}100{r brace} planes with {1/2}{l angle}100{r angle} types of Burgers vectors in a zinc blende structure in InGaAsP lattice matched to InP. These dislocation loops generated only in nonradiative recombination assisted point-defect motion process under intensed laser light, and form the {l angle}100{r angle} type dark line defects in degraded 1.3 {mu}m wavelength laser diodes.

  17. Spin-polaron theory of high-{Tc} superconductivity: I, spin polarons and

    Office of Scientific and Technical Information (OSTI)

    high-{Tc} pairing (Conference) | SciTech Connect Spin-polaron theory of high-{Tc} superconductivity: I, spin polarons and high-{Tc} pairing Citation Details In-Document Search Title: Spin-polaron theory of high-{Tc} superconductivity: I, spin polarons and high-{Tc} pairing The concept of a spin polaron is introduced and contrasted with the more familiar ionic polaron picture. A brief review of aspects of ionic bipolaronic superconductivity is given with particular emphasis on the real-space

  18. Angular dependent study on ferromagnetic resonance and spin excitations by spin rectification

    SciTech Connect (OSTI)

    Zhang, Yichao; Fan, Xiaolong Zhao, Xiaobing; Rao, Jinwei; Zhou, Hengan; Guo, Dangwei; Xue, Desheng; Gui, Y. S.; Hu, C.-M.

    2015-01-14

    We report angular dependent spin rectification spectra which are applied to studying spin excitations in single permalloy stripe. Based on planar Hall effect, those spin excitations generate special resonant dc Hall voltages, which have been characterized as functions of the amplitude and direction of applied magnetic field. Through high angular resolution 2D mappings, the evolutions of different spin excitation can be directly presented, and the dynamic magnetic parameters such as the gyromagnetic ratio, effective exchange field, as well as the quantized numbers of standing spin waves can be accurately determined through fitting the angular evolution of each resonance.

  19. Single-parameter spin-pumping in driven metallic rings with spin-orbit coupling

    SciTech Connect (OSTI)

    Ramos, J. P.; Apel, V. M.; Foa Torres, L. E. F.; Orellana, P. A.

    2014-03-28

    We consider the generation of a pure spin-current at zero bias voltage with a single time-dependent potential. To such end we study a device made of a mesoscopic ring connected to electrodes and clarify the interplay between a magnetic flux, spin-orbit coupling, and non-adiabatic driving in the production of a spin and electrical current. By using Floquet theory, we show that the generated spin to charge current ratio can be controlled by tuning the spin-orbit coupling.

  20. Unitarity Triangle Angle Measurements at BaBar

    SciTech Connect (OSTI)

    Latham, Thomas E.; /SLAC

    2005-06-30

    We present recent results of measurements of the Unitarity Triangle angles alpha, beta and gamma made with the BaBar detector at the PEP-II asymmetric B factory. We present recent results of measurements of the Unitarity Triangle angles alpha, beta and gamma made with the BaBar detector at the PEP-II asymmetric B factory.

  1. Spin valve effect of the interfacial spin accumulation in yttrium iron garnet/platinum bilayers

    SciTech Connect (OSTI)

    Jin, Lichuan; Zhang, Dainan; Zhang, Huaiwu Tang, Xiaoli; Bai, Feiming; Zhong, Zhiyong; Fan, Xin; Xiao, John Q.

    2014-09-29

    We report the spin valve effect in yttrium iron garnet/platinum (YIG/Pt) bilayers. The spin Hall effect (SHE) generates spin accumulation at the YIG/Pt interface and can be opened/closed by magnetization switching in the electrical insulator YIG. The interfacial spin accumulation was measured in both YIG/Pt and YIG/Cu/Pt structures using a planar Hall configuration. The spin valve effect remained, even after a 2 nm thick Cu layer was inserted between the YIG and Pt layers, which aimed to exclude the induced magnetization at the YIG/Pt interface. The transverse Hall voltage and switching field were dependent on the applied charge current density. The origin of this behavior can be explained by the SHE induced torque exerted on the domain wall, caused by the transfer of the spin angular momentum from the spin-polarized current to the YIG magnetic moment.

  2. Skyrmion creation and annihilation by spin waves

    SciTech Connect (OSTI)

    Liu, Yizhou Yin, Gen; Lake, Roger K.; Zang, Jiadong; Shi, Jing

    2015-10-12

    Single skyrmion creation and annihilation by spin waves in a crossbar geometry are theoretically analyzed. A critical spin-wave frequency is required both for the creation and the annihilation of a skyrmion. The minimum frequencies for creation and annihilation are similar, but the optimum frequency for creation is below the critical frequency for skyrmion annihilation. If a skyrmion already exists in the cross bar region, a spin wave below the critical frequency causes the skyrmion to circulate within the central region. A heat assisted creation process reduces the spin-wave frequency and amplitude required for creating a skyrmion. The effective field resulting from the Dzyaloshinskii-Moriya interaction and the emergent field of the skyrmion acting on the spin wave drive the creation and annihilation processes.

  3. Electric field induced spin-polarized current

    DOE Patents [OSTI]

    Murakami, Shuichi; Nagaosa, Naoto; Zhang, Shoucheng

    2006-05-02

    A device and a method for generating an electric-field-induced spin current are disclosed. A highly spin-polarized electric current is generated using a semiconductor structure and an applied electric field across the semiconductor structure. The semiconductor structure can be a hole-doped semiconductor having finite or zero bandgap or an undoped semiconductor of zero bandgap. In one embodiment, a device for injecting spin-polarized current into a current output terminal includes a semiconductor structure including first and second electrodes, along a first axis, receiving an applied electric field and a third electrode, along a direction perpendicular to the first axis, providing the spin-polarized current. The semiconductor structure includes a semiconductor material whose spin orbit coupling energy is greater than room temperature (300 Kelvin) times the Boltzmann constant. In one embodiment, the semiconductor structure is a hole-doped semiconductor structure, such as a p-type GaAs semiconductor layer.

  4. Versatile spin-polarized electron source

    DOE Patents [OSTI]

    Jozwiak, Chris; Park, Cheol -Hwan; Gotlieb, Kenneth; Louie, Steven G.; Hussain, Zahid; Lanzara, Alessandra

    2015-09-22

    One or more embodiments relate generally to the field of photoelectron spin and, more specifically, to a method and system for creating a controllable spin-polarized electron source. One preferred embodiment of the invention generally comprises: method for creating a controllable spin-polarized electron source comprising the following steps: providing one or more materials, the one or more materials having at least one surface and a material layer adjacent to said surface, wherein said surface comprises highly spin-polarized surface electrons, wherein the direction and spin of the surface electrons are locked together; providing at least one incident light capable of stimulating photoemission of said surface electrons; wherein the photon polarization of said incident light is tunable; and inducing photoemission of the surface electron states.

  5. Spin Hall switching of the magnetization in Ta/TbFeCo structures with bulk perpendicular anisotropy

    SciTech Connect (OSTI)

    Zhao, Zhengyang; Jamali, Mahdi; Smith, Angeline K.; Wang, Jian-Ping

    2015-03-30

    Spin-orbit torques are studied in Ta/TbFeCo/MgO patterned structures, where the ferrimagnetic material TbFeCo provides a strong bulk perpendicular magnetic anisotropy (bulk-PMA) independent of the interfaces. The current-induced magnetization switching in TbFeCo is investigated in the presence of a perpendicular, longitudinal, or transverse field. An unexpected partial-switching phenomenon is observed in the presence of a transverse field unique to our bulk-PMA material. It is found that the anti-damping torque related with spin Hall effect is very strong, and a spin Hall angle is determined to be 0.12. The field-like torque related with Rashba effect is unobservable, suggesting that the interface play a significant role in Rashba-like torque.

  6. Spectral characteristics of time resolved magnonic spin Seebeck...

    Office of Scientific and Technical Information (OSTI)

    Spectral characteristics of time resolved magnonic spin Seebeck effect Citation Details In-Document Search Title: Spectral characteristics of time resolved magnonic spin Seebeck ...

  7. Magnetic and nematic orderings in spin-1 antiferromagnets with...

    Office of Scientific and Technical Information (OSTI)

    Magnetic and nematic orderings in spin-1 antiferromagnets with single-ion anisotropy Citation Details In-Document Search Title: Magnetic and nematic orderings in spin-1 ...

  8. Reduced spin-Hall effects from magnetic proximity (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Reduced spin-Hall effects from magnetic proximity Prev Next Title: Reduced spin-Hall effects from magnetic proximity Authors: Zhang, Wei ; Jungfleisch, Matthias B. ; Jiang, ...

  9. Highlights and Perspectives of the JLab Spin Physics Program...

    Office of Scientific and Technical Information (OSTI)

    Conference: Highlights and Perspectives of the JLab Spin Physics Program Citation Details In-Document Search Title: Highlights and Perspectives of the JLab Spin Physics Program ...

  10. Ferromagnets as pure spin current generators and detectors (Patent...

    Office of Scientific and Technical Information (OSTI)

    Ferromagnets as pure spin current generators and detectors Title: Ferromagnets as pure spin current generators and detectors Provided is a spintronics device. The spintronics can ...

  11. Spin crossover in ferropericlase at high pressure: a seismically...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Spin crossover in ferropericlase at high ... Citation Details In-Document Search Title: Spin crossover in ... Publication Date: 2010-09-20 OSTI Identifier: 1124962 Report ...

  12. Frustration and Glassiness in Spin Models with Cavity-Mediated...

    Office of Scientific and Technical Information (OSTI)

    Frustration and Glassiness in Spin Models with Cavity-Mediated Interactions Title: Frustration and Glassiness in Spin Models with Cavity-Mediated Interactions Authors: ...

  13. Tamil Nadu Spinning Mills Association TASMA | Open Energy Information

    Open Energy Info (EERE)

    Tamil Nadu, India Zip: 624003 Sector: Wind energy Product: Association of spinning mill owners; promoting wind power projects. References: Tamil Nadu Spinning Mills...

  14. Emergence of the Persistent Spin Helix in Semiconductor Quantum...

    Office of Scientific and Technical Information (OSTI)

    Emergence of the Persistent Spin Helix in Semiconductor Quantum Wells Citation Details In-Document Search Title: Emergence of the Persistent Spin Helix in Semiconductor Quantum ...

  15. Dirac semimetal films as spin conductors on topological substrates...

    Office of Scientific and Technical Information (OSTI)

    Dirac semimetal films as spin conductors on topological substrates Citation Details In-Document Search Title: Dirac semimetal films as spin conductors on topological substrates ...

  16. Dirac semimetal films as spin conductors on topological substrates...

    Office of Scientific and Technical Information (OSTI)

    Publisher's Accepted Manuscript: Dirac semimetal films as spin conductors on topological substrates Title: Dirac semimetal films as spin conductors on topological substrates ...

  17. Spin Superstructure and Noncoplanar Ordering in Metallic Pyrochlore...

    Office of Scientific and Technical Information (OSTI)

    Spin Superstructure and Noncoplanar Ordering in Metallic Pyrochlore Magnets with Degenerate Orbitals Citation Details In-Document Search Title: Spin Superstructure and Noncoplanar ...

  18. Phase diagram and magnetic excitations of anisotropic spin-one...

    Office of Scientific and Technical Information (OSTI)

    Phase diagram and magnetic excitations of anisotropic spin-one magnets Citation Details In-Document Search Title: Phase diagram and magnetic excitations of anisotropic spin-one ...

  19. Intrinsic charge and spin conductivities of doped graphene in...

    Office of Scientific and Technical Information (OSTI)

    Intrinsic charge and spin conductivities of doped graphene in the Fermi-liquid regime Prev Next Title: Intrinsic charge and spin conductivities of doped graphene in the ...

  20. Area-dependence of spin-triplet supercurrent in ferromagnetic...

    Office of Scientific and Technical Information (OSTI)

    DOE PAGES Search Results Publisher's Accepted Manuscript: Area-dependence of spin-triplet supercurrent in ferromagnetic Josephson junctions Title: Area-dependence of spin-triplet ...

  1. Composite fermion state of spin-orbit-coupled bosons (Journal...

    Office of Scientific and Technical Information (OSTI)

    Composite fermion state of spin-orbit-coupled bosons Prev Next Title: Composite fermion state of spin-orbit-coupled bosons Authors: Sedrakyan, Tigran A. ; Kamenev, Alex ; ...

  2. Paramagnetic Spin Seebeck Effect (Journal Article) | DOE PAGES

    Office of Scientific and Technical Information (OSTI)

    DOE PAGES Search Results Publisher's Accepted Manuscript: Paramagnetic Spin Seebeck Effect Title: Paramagnetic Spin Seebeck Effect Authors: Wu, Stephen M. ; Pearson, John E. ; ...

  3. Optimization of Spin-Triplet Supercurrent in Ferromagnetic Josephson...

    Office of Scientific and Technical Information (OSTI)

    Optimization of Spin-Triplet Supercurrent in Ferromagnetic Josephson Junctions Prev Next Title: Optimization of Spin-Triplet Supercurrent in Ferromagnetic Josephson Junctions ...

  4. Upper bound on parity-violating neutron spin rotation in {sup 4}He

    SciTech Connect (OSTI)

    Snow, W. M.; Luo, D.; Walbridge, S. B.; Crawford, B. E.; Gan, K.; Micherdzinska, A. M.; Opper, A. K.; Heckel, B. R.; Swanson, H. E.; Sharapov, E. I.; Zhumabekova, V.

    2011-02-15

    We report an upper bound on parity-violating neutron spin rotation in {sup 4}He. This experiment is the most sensitive search for neutron-weak optical activity yet performed and represents a significant advance in precision in comparison to past measurements in heavy nuclei. The experiment was performed at the NG-6 slow-neutron beamline at the National Institute of Standards and Technology (NIST) Center for Neutron Research. Our result for the neutron spin rotation angle per unit length in {sup 4}He is d{phi}/dz=[+1.7{+-}9.1(stat.){+-}1.4(sys.)]x10{sup -7} rad/m. The statistical uncertainty is smaller than current estimates of the range of possible values of d{phi}/dz in n+{sup 4}He.

  5. Spin disorder in maghemite nanoparticles investigated using polarized neutrons and nuclear resonant scattering

    SciTech Connect (OSTI)

    Herlitschke, Marcus; Disch, Sabrina; Sergueev, I.; Schlage, Kai; Wetterskog, Erik; Bergstrom, Lennart; Hermann, Raphael P.

    2016-01-01

    The manuscript reports the investigation of spin disorder in maghemite nanoparticles of different shape by a combination of polarized small-angle neutron scattering (SANSPOL) and nuclear forward scattering (NFS) techniques. Both methods are sensitive to magnetization on the nanoscale. SANSPOL allows for investigation of the particle morphology and spatial magnetization distribution and NFS extends this nanoscale information to the atomic scale, namely the orientation of the hyperfine field experienced by the iron nuclei. The studied nanospheres and nanocubes with diameters of 7.4nm and 10.6 nm, respectively, exhibit a significant spin disorder. This effect leads to a reduction of the magnetization to 44% and 58% of the theoretical maghemite bulk value, observed consistently by both techniques.

  6. Spin disorder in maghemite nanoparticles investigated using polarized neutrons and nuclear resonant scattering

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

    Herlitschke, Marcus; Disch, Sabrina; Sergueev, I.; Schlage, Kai; Wetterskog, Erik; Bergstrom, Lennart; Hermann, Raphael P.

    2016-01-01

    The manuscript reports the investigation of spin disorder in maghemite nanoparticles of different shape by a combination of polarized small-angle neutron scattering (SANSPOL) and nuclear forward scattering (NFS) techniques. Both methods are sensitive to magnetization on the nanoscale. SANSPOL allows for investigation of the particle morphology and spatial magnetization distribution and NFS extends this nanoscale information to the atomic scale, namely the orientation of the hyperfine field experienced by the iron nuclei. The studied nanospheres and nanocubes with diameters of 7.4nm and 10.6 nm, respectively, exhibit a significant spin disorder. This effect leads to a reduction of the magnetization tomore » 44% and 58% of the theoretical maghemite bulk value, observed consistently by both techniques.« less

  7. Detection of in-depth helical spin structures by planar Hall effect

    SciTech Connect (OSTI)

    Basaran, Ali C. Guénon, S.; Schuller, Ivan K.; Morales, R.

    2015-06-22

    We developed a method to determine the magnetic helicity and to study reversal mechanisms in exchange biased nanostructures using Planar Hall Effect (PHE). As a test case, we use an in-depth helical spin configuration that occurs during magnetization reversal in exchange coupled Ni/FeF{sub 2} heterostructures. We show the way to induce and determine the sign of the helicity from PHE measurements on a lithographically patterned cross. The helicity sign can be controlled by the angle between the externally applied magnetic field and a well-defined unidirectional anisotropy axis. Furthermore, the PHE signal reveals complex reversal features due to small deviations of the local unidirectional anisotropy axes from the crystallographic easy axis. The simulations using an incomplete domain wall model are in excellent agreement with the experimental data. These studies show that helical spin formations in nanomagnetic systems can be studied using laboratory-based magnetotransport.

  8. Enhanced spin Hall effect by electron correlations in CuBi alloys

    SciTech Connect (OSTI)

    Gu, Bo Xu, Zhuo; Mori, Michiyasu; Maekawa, Sadamichi; Ziman, Timothy

    2015-05-07

    A recent experiment in CuBi alloys obtained a large spin Hall angle (SHA) of −0.24 (Niimi et al., Phys. Rev. Lett. 109, 156602 (2012)). We find that the SHA can be dramatically enhanced by Bi impurities close to the Cu surface. The mechanisms of this enhancement are two-fold. One is that the localized impurity state on surface has a decreased hybridization and combined with Coulomb correlation effect. The other comes from the low-dimensional state of conduction electrons on surface, which results in a further enhancement of skew scattering by impurities. Furthermore, we note that a discrepancy in sign of SHA between the experiment and previous theories is simply caused by different definitions of SHA. This re-establishes skew scattering as the essential mechanism underlying the spin Hall effect in CuBi alloys.

  9. Limits to dark matter annihilation cross-section from a combined analysis of MAGIC and Fermi-LAT observations of dwarf satellite galaxies

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

    Ahnen, M. L.

    2016-02-16

    Here, we present the first joint analysis of gamma-ray data from the MAGIC Cherenkov telescopes and the Fermi Large Area Telescope (LAT) to search for gamma-ray signals from dark matter annihilation in dwarf satellite galaxies. We combine 158 hours of Segue 1 observations with MAGIC with 6-year observations of 15 dwarf satellite galaxies by the Fermi-LAT. We obtain limits on the annihilation cross-section for dark matter particle masses between 10 GeV and 100 TeV - the widest mass range ever explored by a single gamma-ray analysis. These limits improve on previously published Fermi-LAT and MAGIC results by up to amore » factor of two at certain masses. Our new inclusive analysis approach is completely generic and can be used to perform a global, sensitivity-optimized dark matter search by combining data from present and future gamma-ray and neutrino detectors.« less

  10. Cross-correlation spin noise spectroscopy of heterogeneous interacting spin systems

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

    Roy, Dibyendu; Yang, Luyi; Crooker, Scott A.; Sinitsyn, Nikolai A.

    2015-04-30

    Interacting multi-component spin systems are ubiquitous in nature and in the laboratory. As such, investigations of inter-species spin interactions are of vital importance. Traditionally, they are studied by experimental methods that are necessarily perturbative: e.g., by intentionally polarizing or depolarizing one spin species while detecting the response of the other(s). Here, we describe and demonstrate an alternative approach based on multi-probe spin noise spectroscopy, which can reveal inter-species spin interactions - under conditions of strict thermal equilibrium - by detecting and cross-correlating the stochastic fluctuation signals exhibited by each of the constituent spin species. Specifically, we consider a two-component spinmore » ensemble that interacts via exchange coupling, and we determine cross-correlations between their intrinsic spin fluctuations. The model is experimentally confirmed using “two-color” optical spin noise spectroscopy on a mixture of interacting Rb and Cs vapors. Noise correlations directly reveal the presence of inter-species spin exchange, without ever perturbing the system away from thermal equilibrium. These non-invasive and noise-based techniques should be generally applicable to any heterogeneous spin system in which the fluctuations of the constituent components are detectable.« less