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Title: Optical spin polarization and Hanle effect in GaAsSb: Temperature dependence

Abstract

Continuous-wave optical orientation spectroscopy and the Hanle effect are used to investigate the optical spin polarization and spin dephasing time (gT{sub s}) in GaAsSb with a Sb concentration of ∼6% as a function of temperature. Optical and spin polarizations up to ∼21% were achieved at ∼120 K, and the scaled spin lifetime gT{sub s} decreased monotonously from ∼1.5 ns at 5 K to ∼20 ps at 200 K. We demonstrate that the spin properties of GaAs could be modified by incorporating a small percentage of Sb into it, as a result of an increase in the spin–orbit interactions.

Authors:
; ; ; ;  [1]
  1. National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China)
Publication Date:
OSTI Identifier:
22310949
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTIMONY COMPOUNDS; ARSENIC COMPOUNDS; GALLIUM ARSENIDES; GALLIUM COMPOUNDS; LIFETIME; L-S COUPLING; POLARIZATION; SPECTROSCOPY; SPIN; SPIN ORIENTATION; TEMPERATURE DEPENDENCE

Citation Formats

Qiu, Weiyang, Wang, Xingjun, E-mail: xjwang@mail.sitp.ac.cn, E-mail: luwei@mail.sitp.ac.cn, Chen, Pingping, Li, Ning, and Lu, Wei, E-mail: xjwang@mail.sitp.ac.cn, E-mail: luwei@mail.sitp.ac.cn. Optical spin polarization and Hanle effect in GaAsSb: Temperature dependence. United States: N. p., 2014. Web. doi:10.1063/1.4893981.
Qiu, Weiyang, Wang, Xingjun, E-mail: xjwang@mail.sitp.ac.cn, E-mail: luwei@mail.sitp.ac.cn, Chen, Pingping, Li, Ning, & Lu, Wei, E-mail: xjwang@mail.sitp.ac.cn, E-mail: luwei@mail.sitp.ac.cn. Optical spin polarization and Hanle effect in GaAsSb: Temperature dependence. United States. doi:10.1063/1.4893981.
Qiu, Weiyang, Wang, Xingjun, E-mail: xjwang@mail.sitp.ac.cn, E-mail: luwei@mail.sitp.ac.cn, Chen, Pingping, Li, Ning, and Lu, Wei, E-mail: xjwang@mail.sitp.ac.cn, E-mail: luwei@mail.sitp.ac.cn. Mon . "Optical spin polarization and Hanle effect in GaAsSb: Temperature dependence". United States. doi:10.1063/1.4893981.
@article{osti_22310949,
title = {Optical spin polarization and Hanle effect in GaAsSb: Temperature dependence},
author = {Qiu, Weiyang and Wang, Xingjun, E-mail: xjwang@mail.sitp.ac.cn, E-mail: luwei@mail.sitp.ac.cn and Chen, Pingping and Li, Ning and Lu, Wei, E-mail: xjwang@mail.sitp.ac.cn, E-mail: luwei@mail.sitp.ac.cn},
abstractNote = {Continuous-wave optical orientation spectroscopy and the Hanle effect are used to investigate the optical spin polarization and spin dephasing time (gT{sub s}) in GaAsSb with a Sb concentration of ∼6% as a function of temperature. Optical and spin polarizations up to ∼21% were achieved at ∼120 K, and the scaled spin lifetime gT{sub s} decreased monotonously from ∼1.5 ns at 5 K to ∼20 ps at 200 K. We demonstrate that the spin properties of GaAs could be modified by incorporating a small percentage of Sb into it, as a result of an increase in the spin–orbit interactions.},
doi = {10.1063/1.4893981},
journal = {Applied Physics Letters},
number = 8,
volume = 105,
place = {United States},
year = {Mon Aug 25 00:00:00 EDT 2014},
month = {Mon Aug 25 00:00:00 EDT 2014}
}
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