English
Related papers

Related papers: Spontaneous spin polarization in doped semiconduct…

200 papers

We study the magnetic phases of two coupled two-dimensional electron gases in order to determine under what circumstances these phases may occur in real semiconductor quantum wells and what the experimental properties of the broken-symmetry…

Condensed Matter · Physics 2007-05-23 P. I. Tamborenea , R. J. Radtke , S. Das Sarma

The conditions for a spontaneous spin polarization in a quantum wire positioned in a zero magnetic field are analyzed under weak population of one-dimensional subbands that gives rise to the efficient quenching of the kinetic energy by the…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 N. T. Bagraev , V. K. Ivanov , L. E. Klyachkin , I. A. Shelykh

An existence of predominant symmetrical spin configuration (spin polarised phase) and "diluted" density of states (pseudo-gap) in a layer under the Fermi level in a quantum wire is predicted. The condition of cross-over from non-polarised…

Strongly Correlated Electrons · Physics 2009-10-31 V. V'yurkov , A. Vetrov

We present a complete description of spin injection and detection in Fe/Al_xGa_{1-x}As/GaAs heterostructures for temperatures from 2 to 295 K. Measurements of the steady-state spin polarization in the semiconductor indicate three…

Materials Science · Physics 2009-11-10 C. Adelmann , X. Lou , J. Strand , C. J. Palmstrom , P. A. Crowell

High frequency (ac) conductivity in the single quantum well AlGaAs/GaAs/AlGaAs with high mobility was investigated by contactless acoustic methods in the fractional quantum Hall effect regime in perpendicular and tilted magnetic fields. We…

Mesoscale and Nanoscale Physics · Physics 2015-11-23 I. L. Drichko , I. Yu. Smirnov , A. V. Suslov , L. N. Pfeiffer , K. W. West

The total energy of a quasi-one-dimensional electron system is calculated using density functional theory. It is shown that spontaneous ferromagnetic state in quantum wire occurs at low one-dimensional electron density. The critical…

Mesoscale and Nanoscale Physics · Physics 2013-01-14 A. A. Vasilchenko

We evaluate the charge and longitudinal spin response functions of a two-dimensional electron gas with $e^2/r$ interactions in an arbitrary state of spin polarization, using a structurally self-consistent approach to treat exchange and…

Strongly Correlated Electrons · Physics 2015-06-24 B. Davoudi , M. P. Tosi

Density-functional calculations using an exact exchange potential for a two-dimensional electron gas (2DEG) formed in a GaAs single quantum well predict the existence of a spin-polarized phase, when an excited subband becomes slightly…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 A. R. Goñi , P. Giudici , F. A. Reboredo , C. R. Proetto , C. Thomsen , K. Eberl , M. Hauser

We demonstrate the epitaxial growth of optical-quality electrically-gated III-V ferromagnetic quantum structures. Photoluminescence spectroscopy reveals that initially unpolarized photoexcited holes in a GaAs quantum well become…

Materials Science · Physics 2007-05-23 R. C. Myers , A. C. Gossard , D. D. Awschalom

The magnetic order resulting from a confinement-adapted Ruderman-Kittel-Kasuya-Yosida indirect exchange between magnetic moments in the metallic phase of a AlAs/Ga(1-x)Mn(x)As quantum well is studied by Monte Carlo simulation. This coupling…

Condensed Matter · Physics 2009-10-31 M. A. Boselli , A. Ghazali , I. C. da Cunha Lima

The backscattering process of injected electrons on exchange-splitted levels of quantum well (QW) in ferromagnetic metal / insulator / semiconductor heterostructure is studied. It is found that, if one of the exchange-splitted levels lies…

Mesoscale and Nanoscale Physics · Physics 2014-06-20 Leonid Lutsev

A mesoscopic spin valve is used to determine the effective spin polarization of electrons tunneling from and into ferromagnetic transition metals at finite voltages. The tunneling spin polarization from the ferromagnet (FM) slowly decreases…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 S. O. Valenzuela , D. J. Monsma , C. M. Marcus , V. Narayanamurti , M. Tinkham

We study the spin and charge dynamics of electrons in n-doped II--VI semiconductor multiple quantum wells when one or more quantum wells are doped with Mn. The interplay between strongly nonlinear inter-well charge transport and the large…

Condensed Matter · Physics 2009-11-07 Manuel Bejar , David Sanchez , Gloria Platero , A. H. MacDonald

Sharp localization transitions of chiral edge states in disordered quantum wires, subject to strong magnetic field, are shown to be driven by crossovers from two- to one-dimensional localization of bulk states. As a result, the two-terminal…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 S. Kettemann , B. Kramer , T. Ohtsuki

We employ optical pump-probe spectroscopy to investigate the voltage dependence of spontaneous electron and nuclear spin polarizations in hybrid MnAs/n-GaAs and Fe/n-GaAs Schottky diodes. Through the hyperfine interaction, nuclear spin…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 R. J. Epstein , J. Stephens , M. Hanson , Y. Chye , A. C. Gossard , P. M. Petroff , D. D. Awschalom

Spin splitting in the integer quantum Hall effect is investigated for a series of Al$_{x}$Ga$_{1-x}$As/GaAs heterojunctions and quantum wells. Magnetoresistance measurements are performed at mK temperature to characterize the electronic…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 B. A. Piot , D. K. Maude , M. Henini , Z. R. Wasilewski , K. J. Friedland , R. Hey , K. H. Ploog , A. I. Toropov , R. Airey , G. Hill

The experimental studies of the paramagnetic-antiferromagnetic phase transition through M\"{o}ssbauer spectroscopy and measurements of temperature and field dependencies of magnetic susceptibility in the layered Cu$_{0.15}$Fe$_{0.85}$PS$_3$…

Computational Physics · Physics 2023-01-05 V. Pashchenko , O. Bludov , D. Baltrunas , K. Mazeika , S. Motria , K. Glukhov , Yu. Vysochanskii

By measuring electron tunneling between a ferromagnet and individual energy levels in an aluminum quantum dot, we show how spin-resolved quantum states can be used as filters to determine spin-dependent tunneling rates. We also observe…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Mandar M. Deshmukh , D. C. Ralph

We report on experiments in which a spin-polarized current is injected from a $GaMnAs$ ferromagnetic electrode into a $GaAs$ quantum well through an AlAs barrier. The resulting spin polarization in the GaAs well is detected by measuring how…

Materials Science · Physics 2009-11-07 R. Mattana , J. -M. George , H. Jaffres , F. Nguyen Van Dau , A. Fert , B. Lepine , A. Guivarc'h , G. Jezequel

We provide a microscopic theory for the Doppler velocimetry of spin propagation in the presence of spatial inhomogeneity, driving electric field and the spin orbit coupling in semiconductor quantum wells in a wide range of temperature…

Mesoscale and Nanoscale Physics · Physics 2012-11-12 M. Q. Weng , M. W. Wu
‹ Prev 1 2 3 10 Next ›