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Related papers: Spin Injection and Relaxation in Ferromagnet-Semic…

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Highly accurate numerical results of phonon-induced two-electron spin relaxation in silicon double quantum dots are presented. The relaxation, enabled by spin-orbit coupling and the nuclei of $^{29}$Si (natural or purified abundance), are…

Mesoscale and Nanoscale Physics · Physics 2013-02-01 Martin Raith , Peter Stano , Jaroslav Fabian

Optical pump-probe measurements of spin-dynamics at temperatures down to 1.5K are described for a series of (001)-oriented GaAs/AlGaAs quantum well samples containing high mobility two-dimensional electron gases (2DEGs). For well widths…

Other Condensed Matter · Physics 2009-11-13 W. J. H. Leyland , R. T. Harley , M. Henini , D. Taylor , A. J. Shields , I. Farrer , D. A. Ritchie

Exciton spin relaxation is investigated in single epitaxially grown semiconductor quantum dots in order to test the expected spin relaxation quenching in this system. We study the polarization anisotropy of the photoluminescence signal…

We have shown that electron spin density can be generated by a dc current flowing across a $pn$ junction with an embedded asymmetric quantum well. Spin polarization is created in the quantum well by radiative electron-hole recombination…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 A. G. Mal'shukov , K. A. Chao

Recent experiments have demonstrated long spin lifetimes in uniformly n-doped quantum wells. The spin dynamics of exciton, localized, and conduction spins are important for understanding these systems. We explain experimental behavior by…

Mesoscale and Nanoscale Physics · Physics 2012-05-02 N. J. Harmon , W. O. Putikka , R. Joynt

We study the temperature dependence of the electrical conductance of a clean strongly interacting quantum wire in the presence of a helical nuclear spin order. The nuclear spin helix opens a temperature-dependent partial gap in the electron…

Mesoscale and Nanoscale Physics · Physics 2017-04-05 Pavel Aseev , Jelena Klinovaja , Daniel Loss

We have studied theoretically the electron spin relaxation in semiconductor quantum dots via interaction with nuclear spins. The relaxation is shown to be determined by three processes: (i) -- the precession of the electron spin in the…

Condensed Matter · Physics 2009-11-07 I. A. Merkulov , Al. L. Efros , M. Rosen

Epitaxial ferromagnetic metal - semiconductor heterostructures are investigated using polarization-dependent electroabsorption measurements on GaAs p-type and n-type Schottky diodes with embedded In1-xGaxAs quantum wells. We have conducted…

Condensed Matter · Physics 2009-11-07 A. F. Isakovic , D. M. Carr , J. Strand , B. D. Schultz , C. J. Palmstrom , P. A. Crowell

We have studied the magnetic and transport properties of an ultra-low-resistivity two-dimensional electron system in a Si/SiGe quantum well. The spin polarization increases linearly with the in-plane magnetic field and the enhancement of…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Tohru Okamoto , Mitsuaki Ooya , Kunio Hosoya , Shinji Kawaji

We have studied spin dephasing in a high-mobility two-dimensional electron system (2DES), confined in a GaAs/AlGaAs quantum well grown in the [110] direction, using the resonant spin amplification (RSA) technique. From the characteristic…

Materials Science · Physics 2013-05-30 M. Griesbeck , M. M. Glazov , E. Ya. Sherman , D. Schuh , W. Wegscheider , C. Schüller , T. Korn

Owing to their integer spin, exciton-polaritons in microcavities can be used for observation of non-equilibrium Bose-Einstein condensation in solid state. However, spin-related phenomena of such condensates are difficult to explore due to…

The thermal conductivity of electron-doped Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ single crystals is investigated below 200K, with an emphasis on the behavior near the magnetic and superconducting (T_c) transition temperatures. An enhancement of…

Superconductivity · Physics 2013-08-09 Andrew F. May , Michael A. McGuire , Jonathan E. Mitchell , Athena S. Sefat , Brian C. Sales

We investigate the electron and hole spin relaxation in an ensemble of self-assembled InAs/In$_{0.53}$Al$_{0.24}$Ga$_{0.23}$As/InP quantum dots with emission wavelengths around $1.5$~$\mu$m by pump-probe Faraday rotation spectroscopy.…

Mesoscale and Nanoscale Physics · Physics 2019-01-01 A. V. Mikhailov , V. V. Belykh , D. R. Yakovlev , P. S. Grigoryev , J. P. Reithmaier , M. Benyoucef , M. Bayer

The spin relaxation time due to the electron-acoustic phonon scattering in GaAs quantum dots is studied after the exact diagonalization of the electron Hamiltonian with the spin-orbit coupling. Different effects such as the magnetic field,…

Condensed Matter · Physics 2012-07-02 J. L. Cheng , M. W. Wu , C. Lü

We consider the spin injection from Fe into ZnSe and GaAs in the ballistic limit. By means of the ab initio SKKR method we calculate the ground state properties of epitaxial Fe|ZnSe(001) and Fe|GaAs(001) heterostructures. Three injection…

Condensed Matter · Physics 2009-11-07 O. Wunnicke , Ph. Mavropoulos , R. Zeller , P. H. Dederichs , D. Grundler

In order to enhance spin injection efficiency from ferromagnetic (FM) metal into a two-dimensional electron gas (2DEG), we introduce another FM metal and two tunnel barriers (I) between them to investigate the current polarization in such…

Materials Science · Physics 2007-05-23 Jun Wang , D. Y. Xing , H. B. Sun

We report theoretical and experimental studies of ambipolar spin diffusion in a semiconductor. A circularly polarized laser pulse is used to excite spin-polarized carriers in a GaAs multiple quantum well sample at 80 K. Diffusion of…

Mesoscale and Nanoscale Physics · Physics 2009-03-31 Hui Zhao , Matt Mower , G. Vignale

Spin relaxation is investigated theoretically in two-dimensional systems. Various semiconductor structures of both n- and p-types are studied in detail. The most important spin relaxation mechanisms are considered. The spin relaxation times…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 N. S. Averkiev , L. E. Golub , M. Willander

Utilizing time-resolved Kerr rotation techniques, we have investigated the spin dynamics of a high mobility, low density two dimensional electron gas in a GaAs/Al0:35Ga0:65As heterostructure in dependence on temperature from 1.5 K to 30 K.…

Other Condensed Matter · Physics 2009-11-13 X. Z. Ruan , H. H. Luo , Yang Ji , Z. Y. Xu , V. Umansky

Spin injection efficiency based on conventional ferromagnet (or half-metallic ferromagnet) /semiconductor is greatly limited by the Schmidt obstacle due to conductivity mismatch, here we proposed that by replacing the metallic injectors…

Mesoscale and Nanoscale Physics · Physics 2014-12-01 G. Z. Xu , W. H. Wang , X. M. Zhang , Y. Wang , E. K. Liu , X. K. Xi , G. H. Wu