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Title: Carrier relaxation in (In,Ga)As quantum dots with magnetic field-induced anharmonic level structure

Abstract

Sophisticated models have been worked out to explain the fast relaxation of carriers into quantum dot ground states after non-resonant excitation, overcoming the originally proposed phonon bottleneck. We apply a magnetic field along the quantum dot heterostructure growth direction to transform the confined level structure, which can be approximated by a Fock–Darwin spectrum, from a nearly equidistant level spacing at zero field to strong anharmonicity in finite fields. This changeover leaves the ground state carrier population rise time unchanged suggesting that fast relaxation is maintained upon considerable changes of the level spacing. This corroborates recent models explaining the relaxation by polaron formation in combination with quantum kinetic effects.

Authors:
;  [1]
  1. Experimentelle Physik 2, TU Dortmund, D-44221 Dortmund (Germany)
Publication Date:
OSTI Identifier:
22590579
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 1; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; EXCITATION; GROUND STATES; MAGNETIC FIELDS; PHONONS; POLARONS; QUANTUM DOTS; RELAXATION; SPECTRA

Citation Formats

Kurtze, H., and Bayer, M. Carrier relaxation in (In,Ga)As quantum dots with magnetic field-induced anharmonic level structure. United States: N. p., 2016. Web. doi:10.1063/1.4955459.
Kurtze, H., & Bayer, M. Carrier relaxation in (In,Ga)As quantum dots with magnetic field-induced anharmonic level structure. United States. doi:10.1063/1.4955459.
Kurtze, H., and Bayer, M. 2016. "Carrier relaxation in (In,Ga)As quantum dots with magnetic field-induced anharmonic level structure". United States. doi:10.1063/1.4955459.
@article{osti_22590579,
title = {Carrier relaxation in (In,Ga)As quantum dots with magnetic field-induced anharmonic level structure},
author = {Kurtze, H. and Bayer, M.},
abstractNote = {Sophisticated models have been worked out to explain the fast relaxation of carriers into quantum dot ground states after non-resonant excitation, overcoming the originally proposed phonon bottleneck. We apply a magnetic field along the quantum dot heterostructure growth direction to transform the confined level structure, which can be approximated by a Fock–Darwin spectrum, from a nearly equidistant level spacing at zero field to strong anharmonicity in finite fields. This changeover leaves the ground state carrier population rise time unchanged suggesting that fast relaxation is maintained upon considerable changes of the level spacing. This corroborates recent models explaining the relaxation by polaron formation in combination with quantum kinetic effects.},
doi = {10.1063/1.4955459},
journal = {Applied Physics Letters},
number = 1,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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