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Title: Effects of spin diffusion on electron spin relaxation time measured with a time-resolved microscopic photoluminescence technique

Abstract

We performed measurements at room temperature for a GaAs/AlGaAs multiple quantum well grown on GaAs(110) using a time-resolved microscopic photoluminescence (micro-PL) technique to find what effects spin diffusion had on the measured electron spin relaxation time, τ{sub s}, and developed a method of estimating the spin diffusion coefficient, D{sub s}, using the measured data and the coupled drift-diffusion equations for spin polarized electrons. The spatial nonuniformities of τ{sub s} and the initial degree of electron spin polarization caused by the pump intensity distribution inside the focal spot were taken into account to explain the dependence of τ{sub s} on the measured spot size, i.e., a longer τ{sub s} for a smaller spot size. We estimated D{sub s} as ∼100 cm{sup 2}/s, which is similar to a value reported in the literature. We also provided a qualitative understanding on how spin diffusion lengthens τ{sub s} in micro-PL measurements.

Authors:
;  [1]
  1. Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan)
Publication Date:
OSTI Identifier:
22413036
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; ALUMINIUM ARSENIDES; CRYSTAL STRUCTURE; DIFFUSION; DIFFUSION EQUATIONS; ELECTRONS; GALLIUM ARSENIDES; PHOTOLUMINESCENCE; QUANTUM WELLS; RELAXATION TIME; SPIN; SPIN ORIENTATION; TEMPERATURE RANGE 0273-0400 K; TIME RESOLUTION

Citation Formats

Ikeda, Kazuhiro, E-mail: kaz.ikeda@aist.go.jp, and Kawaguchi, Hitoshi. Effects of spin diffusion on electron spin relaxation time measured with a time-resolved microscopic photoluminescence technique. United States: N. p., 2015. Web. doi:10.1063/1.4906847.
Ikeda, Kazuhiro, E-mail: kaz.ikeda@aist.go.jp, & Kawaguchi, Hitoshi. Effects of spin diffusion on electron spin relaxation time measured with a time-resolved microscopic photoluminescence technique. United States. doi:10.1063/1.4906847.
Ikeda, Kazuhiro, E-mail: kaz.ikeda@aist.go.jp, and Kawaguchi, Hitoshi. Sat . "Effects of spin diffusion on electron spin relaxation time measured with a time-resolved microscopic photoluminescence technique". United States. doi:10.1063/1.4906847.
@article{osti_22413036,
title = {Effects of spin diffusion on electron spin relaxation time measured with a time-resolved microscopic photoluminescence technique},
author = {Ikeda, Kazuhiro, E-mail: kaz.ikeda@aist.go.jp and Kawaguchi, Hitoshi},
abstractNote = {We performed measurements at room temperature for a GaAs/AlGaAs multiple quantum well grown on GaAs(110) using a time-resolved microscopic photoluminescence (micro-PL) technique to find what effects spin diffusion had on the measured electron spin relaxation time, τ{sub s}, and developed a method of estimating the spin diffusion coefficient, D{sub s}, using the measured data and the coupled drift-diffusion equations for spin polarized electrons. The spatial nonuniformities of τ{sub s} and the initial degree of electron spin polarization caused by the pump intensity distribution inside the focal spot were taken into account to explain the dependence of τ{sub s} on the measured spot size, i.e., a longer τ{sub s} for a smaller spot size. We estimated D{sub s} as ∼100 cm{sup 2}/s, which is similar to a value reported in the literature. We also provided a qualitative understanding on how spin diffusion lengthens τ{sub s} in micro-PL measurements.},
doi = {10.1063/1.4906847},
journal = {Journal of Applied Physics},
number = 5,
volume = 117,
place = {United States},
year = {Sat Feb 07 00:00:00 EST 2015},
month = {Sat Feb 07 00:00:00 EST 2015}
}
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