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Title: Optical initialization and dynamics of spin in a remotely doped quantum well

Abstract

The excitation of electron spin polarization and coherence by picosecond light pulses and their dynamics in a wide remotely doped quantum well are studied theoretically and experimentally. Assuming that all electrons in the quantum well are localized, the theory considers the resonant interaction of light pulses with the four-level system formed by the electron spins of the ground state and the hole spins of the trion excited state. The theory describes the effects of spontaneous emission, a transverse magnetic field and hole spin relaxation on the dynamics detected by the Kerr rotation of a probe pulse. Time resolved Kerr rotation experiments were carried out on a remotely doped 14 nm GaAs quantum well in the frequency range of optical transitions to the heavy hole (HH) trion and to the light-hole (LH) trion degenerate with the HH exciton. The experiments on the resonant excitation of the HH trion show a very slow heavy hole spin relaxation and, consequently, a weak electron spin polarization after the trion relaxation. In contrast, the resonant excitation of the LH trion/HH exciton results in a fast hole spin relaxation that increases electron spin polarization.

Authors:
; ; ; ;  [1];  [2];  [3]
  1. Naval Research Laboratory, Washington, DC 20375 (United States)
  2. Naval Research Laboratory, Washington, D.C. 20375 (United States)
  3. (United States)
Publication Date:
OSTI Identifier:
20787855
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevB.73.045307; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; DOPED MATERIALS; ELECTRONS; EXCITATION; EXCITED STATES; EXCITONS; GALLIUM ARSENIDES; GROUND STATES; HOLES; MAGNETIC FIELDS; POLARIZATION; PULSES; QUANTUM WELLS; RELAXATION; ROTATION; SEMICONDUCTOR MATERIALS; SPIN; SPIN ORIENTATION; TIME RESOLUTION; VISIBLE RADIATION

Citation Formats

Kennedy, T. A., Scheibner, M., Efros, Al. L., Bracker, A. S., Gammon, D., Shabaev, A., and School of Computational Sciences, George Mason University, Fairfax, Virginia 22030. Optical initialization and dynamics of spin in a remotely doped quantum well. United States: N. p., 2006. Web. doi:10.1103/PHYSREVB.73.0.
Kennedy, T. A., Scheibner, M., Efros, Al. L., Bracker, A. S., Gammon, D., Shabaev, A., & School of Computational Sciences, George Mason University, Fairfax, Virginia 22030. Optical initialization and dynamics of spin in a remotely doped quantum well. United States. doi:10.1103/PHYSREVB.73.0.
Kennedy, T. A., Scheibner, M., Efros, Al. L., Bracker, A. S., Gammon, D., Shabaev, A., and School of Computational Sciences, George Mason University, Fairfax, Virginia 22030. Sun . "Optical initialization and dynamics of spin in a remotely doped quantum well". United States. doi:10.1103/PHYSREVB.73.0.
@article{osti_20787855,
title = {Optical initialization and dynamics of spin in a remotely doped quantum well},
author = {Kennedy, T. A. and Scheibner, M. and Efros, Al. L. and Bracker, A. S. and Gammon, D. and Shabaev, A. and School of Computational Sciences, George Mason University, Fairfax, Virginia 22030},
abstractNote = {The excitation of electron spin polarization and coherence by picosecond light pulses and their dynamics in a wide remotely doped quantum well are studied theoretically and experimentally. Assuming that all electrons in the quantum well are localized, the theory considers the resonant interaction of light pulses with the four-level system formed by the electron spins of the ground state and the hole spins of the trion excited state. The theory describes the effects of spontaneous emission, a transverse magnetic field and hole spin relaxation on the dynamics detected by the Kerr rotation of a probe pulse. Time resolved Kerr rotation experiments were carried out on a remotely doped 14 nm GaAs quantum well in the frequency range of optical transitions to the heavy hole (HH) trion and to the light-hole (LH) trion degenerate with the HH exciton. The experiments on the resonant excitation of the HH trion show a very slow heavy hole spin relaxation and, consequently, a weak electron spin polarization after the trion relaxation. In contrast, the resonant excitation of the LH trion/HH exciton results in a fast hole spin relaxation that increases electron spin polarization.},
doi = {10.1103/PHYSREVB.73.0},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 4,
volume = 73,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
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