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Related papers: Subsecond nuclear spin dynamics in $n$-GaAs

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The spin-memory effect in the GaAs / InGaAs heterostructures with $\delta$<Mn> layer in GaAs barrier have been investigated. The effect consists in spin polarization of Mn atoms due to interaction with photogenerated spin-polarized holes.…

We consider a system of two strongly coupled electron spins in zero magnetic field, each of which is interacting with an individual bath of nuclear spins via the hyperfine interaction. Applying the long spin approximation (LSA) introduced…

Mesoscale and Nanoscale Physics · Physics 2012-07-04 Bjoern Erbe , John Schliemann

We propose a model for spectral diffusion of localized spins in semiconductors due to the dipolar fluctuations of lattice nuclear spins. Each nuclear spin flip-flop is assumed to be independent, the rate for this process being calculated by…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Rogerio de Sousa , S. Das Sarma

In semiconductor quantum dots, the electron hyperfine interaction with the nuclear spin bath is the leading source of spin decoherence at cryogenic temperature. Using high-resolution two-color differential transmission spectroscopy, we…

Mesoscale and Nanoscale Physics · Physics 2015-06-23 G. Moody , M. Feng , C. McDonald , R. P. Mirin , K. L. Silverman

We theoretically study the dynamic polarization of lattice nuclear spins in GaAs double quantum dots containing two electrons. In our prior work [Phys. Rev. Lett. 104, 226807 (2010)] we identified three regimes of long-term dynamics,…

Mesoscale and Nanoscale Physics · Physics 2014-07-28 M. Gullans , J. J. Krich , J. M. Taylor , B. I. Halperin , M. D. Lukin

We develop an extended pump-probe Faraday rotation technique to study the submicrosecond electron spin dynamics with picosecond time resolution in a wide range of magnetic fields. The electron spin dephasing time $T_2^*$ and the…

Mesoscale and Nanoscale Physics · Physics 2017-09-01 V. V. Belykh , E. Evers , D. R. Yakovlev , F. Fobbe , A. Greilich , M. Bayer

We study spin polarization in a split-gate quantum wire focussing on the effect of a realistic smooth potential due to remote donors. Electron interaction and spin effects are included within the density functional theory in the local spin…

Mesoscale and Nanoscale Physics · Physics 2008-04-04 M. Evaldsson , S. Ihnatsenka , I. V. Zozoulenko

We investigate the motion of a domain wall in the presence of a dynamical hyperfine field. At temperature T high compared to the hyperfine coupling, the nuclear spins create a spatially random potential landscape, with dynamics dictated by…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. Dube , P. C. E. Stamp

Nuclear spin polarization is typically generated in GaAs quantum point contacts (QPCs) when an out-of-plane magnetic field gives rise to spin-polarized quantum Hall edge states, and a voltage bias drives transitions between the edge states…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 Y. Ren , W. Yu , S. M. Frolov , J. A. Folk , W. Wegscheider

The dynamics of the coupled electron-nuclear spin system is studied in an ensemble of singly-charged (In,Ga)As/GaAs quantum dots (QDs) using periodic optical excitation at 1 GHz repetition rate. In combination with the electron-nuclei…

Mesoscale and Nanoscale Physics · Physics 2021-08-11 E. Evers , N. E. Kopteva , I. A. Yugova , D. R. Yakovlev , M. Bayer , A. Greilich

We describe measurements of spin dynamics in the two-dimensional electron gas in GaAs/GaAlAs quantum wells. Optical techniques, including transient spin-grating spectroscopy, are used to probe the relaxation rates of spin polarization waves…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 C. P. Weber , J. Orenstein , B. Andrei Bernevig , Shou-Cheng Zhang , Jason Stephens , D. D. Awschalom

We report nearly complete preservation of "spin memory" between optical absorption and photoluminescence (PL) in nanometer slabs of GaSe pumped with up to 0.2 eV excess energy. At cryogenic temperatures, the initial degree of circular…

Mesoscale and Nanoscale Physics · Physics 2015-05-22 Yanhao Tang , Wei Xie , Krishna C. Mandal , John A. McGuire , Chih-Wei Lai

The photoluminescence polarizations of (In,Ga)As/GaAs quantum dots annealed at different temperatures are studied as a function of external magnetic field (Hanle curves). In these dependencies, remarkable resonant features appear due to…

We demonstrate room-temperature spin-polarized ultrafast ($\sim$10 ps) lasing in a highly optically excited GaAs microcavity. This microcavity is embedded with InGaAs multiple quantum wells in which the spin relaxation time is less than 10…

Mesoscale and Nanoscale Physics · Physics 2015-05-22 Feng-kuo Hsu , Wei Xie , Yi-Shan Lee , Sheng-Di Lin , Chih-Wei Lai

We propose a new method for dynamic nuclear polarisation in a quasi one-dimensional quantum wire utilising the spin-orbit interaction, the hyperfine interaction, and a finite source-drain potential difference. In contrast with current…

Mesoscale and Nanoscale Physics · Physics 2008-03-05 V. Tripathi , A. C. H. Cheung , N. R. Cooper

The dynamics of a spin-1/2 particle coupled to a nuclear spin bath through an isotropic Heisenberg interaction is studied, as a model for the spin decoherence in quantum dots. The time-dependent polarization of the central spin is…

Quantum Physics · Physics 2007-06-28 D. D. Bhaktavatsala Rao , V. Ravishankar , V. Subrahmanyam

The nature of the nano-scale environment presents a major challenge for solid-state implementation of spin-based qubits. In this work, a single electron spin in an optically pumped nanometer-sized III-V semiconductor quantum dot is used to…

We present a quantum mechanical theory of optically induced dynamic nuclear polarization applicable to quantum dots and other interacting spin systems. The exact steady state of the optically driven coupled electron-nuclear system is…

Mesoscale and Nanoscale Physics · Physics 2019-02-04 Thomas Nutz , Edwin Barnes , Sophia E. Economou

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

In this work we present a new formalism to evaluate the nuclear spin dynamics driven by hyperfine interaction with non-equilibrium electron spins. To describe the dynamics up to second order in the hyperfine coupling, it suffices to…

Mesoscale and Nanoscale Physics · Physics 2011-07-12 J. Danon , Yu. V. Nazarov