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Title: Coherent spin dynamics of carriers in ferromagnetic semiconductor heterostructures with an Mn δ layer

Abstract

The coherent spin dynamics of carriers in the heterostructures that contain an InGaAs/GaAs quantum well (QW) and an Mn δ layer, which are separated by a narrow GaAs spacer 2–10 nm thick, is comprehensively studied by the magnetooptical Kerr effect method at a picosecond time resolution. The exchange interaction of photoexcited electrons in QW with the ferromagnetic Mn δ layer manifests itself in magnetic-field and temperature dependences of the Larmor precession frequency of electron spins and is found to be very weak (several microelectron volts). Two nonoscillating components related to holes exist apart from an electron contribution to the Kerr signal of polarization plane rotation. At the initial stage, a fast relaxation process, which corresponds to the spin relaxation of free photoexcited holes, is detected in the structures with a wide spacer. The second component is caused by the further spin dephasing of energyrelaxed holes, which are localized at strong QW potential fluctuations in the structures under study. The decay of all contributions to the Kerr signal in time increases substantially when the spacer thickness decreases, which correlates with the enhancement of nonradiative recombination in QW.

Authors:
 [1];  [2];  [3]; ; ;  [4]; ;  [2]
  1. Russian Academy of Sciences, Institute of Solid State Physics (Russian Federation)
  2. Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)
  3. Technische Universität Dortmund, Experimentelle Physik 2 (Germany)
  4. Lobachevskii State University, Nizhny Novgorod Research Physicotechnical Institute (Russian Federation)
Publication Date:
OSTI Identifier:
22617187
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 123; Journal Issue: 3; Other Information: Copyright (c) 2016 Pleiades Publishing, Inc.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CARRIERS; ELECTRONS; EXCHANGE INTERACTIONS; FLUCTUATIONS; GALLIUM ARSENIDES; HOLES; INDIUM COMPOUNDS; KERR EFFECT; LARMOR PRECESSION; LAYERS; MAGNETIC FIELDS; POLARIZATION; QUANTUM WELLS; RECOMBINATION; RELAXATION; SPIN; TEMPERATURE DEPENDENCE; THICKNESS; TIME RESOLUTION

Citation Formats

Zaitsev, S. V., E-mail: szaitsev@issp.ac.ru, Akimov, I. A., Langer, L., Danilov, Yu. A., Dorokhin, M. V., Zvonkov, B. N., Yakovlev, D. R., and Bayer, M.. Coherent spin dynamics of carriers in ferromagnetic semiconductor heterostructures with an Mn δ layer. United States: N. p., 2016. Web. doi:10.1134/S106377611607013X.
Zaitsev, S. V., E-mail: szaitsev@issp.ac.ru, Akimov, I. A., Langer, L., Danilov, Yu. A., Dorokhin, M. V., Zvonkov, B. N., Yakovlev, D. R., & Bayer, M.. Coherent spin dynamics of carriers in ferromagnetic semiconductor heterostructures with an Mn δ layer. United States. doi:10.1134/S106377611607013X.
Zaitsev, S. V., E-mail: szaitsev@issp.ac.ru, Akimov, I. A., Langer, L., Danilov, Yu. A., Dorokhin, M. V., Zvonkov, B. N., Yakovlev, D. R., and Bayer, M.. 2016. "Coherent spin dynamics of carriers in ferromagnetic semiconductor heterostructures with an Mn δ layer". United States. doi:10.1134/S106377611607013X.
@article{osti_22617187,
title = {Coherent spin dynamics of carriers in ferromagnetic semiconductor heterostructures with an Mn δ layer},
author = {Zaitsev, S. V., E-mail: szaitsev@issp.ac.ru and Akimov, I. A. and Langer, L. and Danilov, Yu. A. and Dorokhin, M. V. and Zvonkov, B. N. and Yakovlev, D. R. and Bayer, M.},
abstractNote = {The coherent spin dynamics of carriers in the heterostructures that contain an InGaAs/GaAs quantum well (QW) and an Mn δ layer, which are separated by a narrow GaAs spacer 2–10 nm thick, is comprehensively studied by the magnetooptical Kerr effect method at a picosecond time resolution. The exchange interaction of photoexcited electrons in QW with the ferromagnetic Mn δ layer manifests itself in magnetic-field and temperature dependences of the Larmor precession frequency of electron spins and is found to be very weak (several microelectron volts). Two nonoscillating components related to holes exist apart from an electron contribution to the Kerr signal of polarization plane rotation. At the initial stage, a fast relaxation process, which corresponds to the spin relaxation of free photoexcited holes, is detected in the structures with a wide spacer. The second component is caused by the further spin dephasing of energyrelaxed holes, which are localized at strong QW potential fluctuations in the structures under study. The decay of all contributions to the Kerr signal in time increases substantially when the spacer thickness decreases, which correlates with the enhancement of nonradiative recombination in QW.},
doi = {10.1134/S106377611607013X},
journal = {Journal of Experimental and Theoretical Physics},
number = 3,
volume = 123,
place = {United States},
year = 2016,
month = 9
}
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