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Related papers: Optically controlled spin-polarization memory effe…

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The current-induced spin polarization and momentum-dependent spin-orbit field were measured in In$_{x}$Ga$_{1-x}$As epilayers with varying indium concentrations and silicon doping densities. Samples with higher indium concentrations and…

Mesoscale and Nanoscale Physics · Physics 2017-11-22 M. Luengo-Kovac , S. Huang , D. Del Gaudio , J. Occena , R. S. Goldman , R. Raimondi , V. Sih

The spin dynamics in a broad range of systems can be studied using circularly polarized optical excitation with alternating helicity. The dependence of spin polarization on the frequency of helicity alternation, known as the spin inertia…

Mesoscale and Nanoscale Physics · Physics 2018-09-19 E. A. Zhukov , E. Kirstein , D. S. Smirnov , D. R. Yakovlev , M. M. Glazov , D. Reuter , A. D. Wieck , M. Bayer , A. Greilich

Spin splitting of photoelectrons in p-type and electrons in n-type III-V Mn-based diluted magnetic semiconductors is studied theoretically. It is demonstrated that the unusual sign and magnitude of the apparent s-d exchange integral…

Materials Science · Physics 2009-04-16 C. Sliwa , T. Dietl

We have made quantitative measurements of the spin polarization of two-dimensional (2D) GaAs (100) electrons and GaAs (311)A holes, as a function of an in-plane magnetic field. The functional form of the in-plane magnetoresistance is shown…

Mesoscale and Nanoscale Physics · Physics 2015-06-24 E. Tutuc , E. P. De Poortere , S. J. Papadakis , M. Shayegan

We investigate exciton spin memory in individual InAs/GaAs self-assembled quantum dots via optical alignment and conversion of exciton polarization in a magnetic field. Quasiresonant phonon-assisted excitation is successfully employed to…

Materials Science · Physics 2009-11-13 K. Kowalik , O. Krebs , A. Lemaître , J. A. Gaj , P. Voisin

We show that through the resonant optical excitation of spin-polarized excitons into CdMnTe magnetic quantum dots, we can induce a macroscopic magnetization of the Mn impurities. We observe very broad (4 meV linewidth) emission lines of…

Soft Condensed Matter · Physics 2009-11-10 T. Gurung , S. Mackowski , H. E. Jackson , L. M. Smith , W. Heiss , J. Kossut , G. Karczewski

We investigate in micro-photoluminescence experiments the dynamical nuclear polarization in individual InGaAs quantum dots. Experiments carried out in an applied magnetic field of 2T show that the nuclear polarization achieved through the…

Other Condensed Matter · Physics 2009-11-13 B. Urbaszek , P. -F. Braun , X. Marie , O. Krebs , A. Lemaitre , P. Voisin , T. Amand

The hyperfine interaction of an electron with nuclei in the annealed self-assembled InAs/GaAs quantum dots is theoretically analyzed. For this purpose, the annealing process, and energy structure of the quantum dots are numerically modeled.…

Other Condensed Matter · Physics 2010-08-05 M. Yu. Petrov , I. V. Ignatiev , S. V. Poltavtsev , A. Greilich , A. Bauschulte , D. R. Yakovlev , M. Bayer

We optically generate electron spins in semiconductors and apply an external magnetic field perpendicularly to them. Time-resolved photoluminescence measurements, pumped with a circularly polarized light, are performed to study the spin…

Applied Physics · Physics 2018-05-02 M. Idrish Miah

Using the emission of the positively charged exciton as a probe, we analyze the dynamics of the optical pumping and the dynamics of the relaxation of a Mn spin exchange-coupled with a confined hole spin in a II-VI semiconductor quantum dot.…

Mesoscale and Nanoscale Physics · Physics 2015-06-22 B. Varghese , H. Boukari , L. Besombes

We describe a new means for electrically creating spin polarization in semiconductors. In contrast to spin injection of electrons by tunneling through a reverse-biased Schottky barrier, we observe spin accumulation at the…

Materials Science · Physics 2009-11-10 J. Stephens , J. Berezovsky , J. P. McGuire , L. J. Sham , A. C. Gossard , D. D. Awschalom

We report magnetization and magetoresistance measurements in hybrid ferromagnetic metal/semiconductor heterostructures comprised of MnAs/(Ga,Mn)As bilayers. Our measurements show that the (metallic) MnAs and (semiconducting) (Ga,Mn)As…

Materials Science · Physics 2010-07-14 M. Zhu , M. J. Wilson , B. L. Sheu , P. Mitra , P. Schiffer , N. Samarth

We investigate the dynamic nuclear polarization from the hyperfine interaction between nonequilibrium electronic spins and nuclear spins coupled to them in semiconductor nanostructures. We derive the time and position dependence of the…

Materials Science · Physics 2007-05-23 Ionel Tifrea , Michael E. Flatte

{\bf Purpose}: Manipulation of the radio-sensitivity of the nucleotide-base driven by the spin blockade mechanism of diffusive free radicals against ionizing radiation. {\bf Materials and methods}: We theoretically propose a mechanism which…

Chemical Physics · Physics 2009-07-28 Ramin M. Abolfath

We study the controlled introduction of defects in GaMnAs by irradiating the samples with energetic ion beams, which modify the magnetic properties of the DMS. Our study focuses on the low-carrier-density regime, starting with as-grown…

Disordered Systems and Neural Networks · Physics 2010-06-14 E. H. C. P. Sinnecker , G. M. Penello , T. G. Rappoport , M. M. Sant'Anna , D. E. R. Souza , M. P. Pires , X. Liu , J. K. Furdyna

Magnetic materials with negative spin polarization have attracted attention for their potential to increase the design freedom of spintronic devices. This study investigated the effects of off-stoichiometry on the atomic ordering,…

We directly observe and spatially map an optical analog of the Magnus effect, where intrinsic spin-orbit-like coupling of light generates a spin-dependent transverse displacement of the atom-light interaction profile for a $^{40}$Ca$^+$…

We demonstrate methods to locally control the spin rotation of moving electrons in a GaAs channel. The Larmor frequency of optically-injected spins is modulated when the spins are dragged through a region of spin-polarized nuclei created at…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 M. E. Nowakowski , G. D. Fuchs , S. Mack , N. Samarth , D. D. Awschalom

The effect of hyperfine interaction on the room-temperature defect-enabled spin filtering effect in GaNAs alloys is investigated both experimentally and theoretically through a master equation approach based on the hyperfine and Zeeman…

Mesoscale and Nanoscale Physics · Physics 2015-06-17 C. Sandoval-Santana , A. Balocchi , T. Amand , J. C. Harmand , A. Kunold , X. Marie

Spatially indirect Type-II band alignment in magnetically-doped quantum dot (QD) structures provides unexplored opportunities to control the magnetic interaction between carrier wavefunction in the QD and magnetic impurities. Unlike the…

Mesoscale and Nanoscale Physics · Physics 2018-01-17 P. Zhang , T. Norden , J. M. Pientka , R. Oszwałdowski , A. Najafi , B. Barman , Y. Tsai , W-C. Fan , W-C. Chou , J. E. Han , I. Žutić , B. D. McCombe , A. Petrou
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