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Title: Resonances related to an array of InAs quantum dots and controlled by an external electric field

Abstract

Photoluminescence of multilayer structures with InAs quantum dots grown in the p-n junction in GaAs by molecular-beam epitaxy is studied. Formation of vertical columns of quantum dots is verified by the data of transmission electron microscopy. It is shown that a natural increase in the size of quantum dots from layer to layer brings about their vertical coalescence at the upper part of a column. An unbalance of electronic levels caused by the enlargement of quantum dots was compensated by an external electric field, so that the resonance of ground electronic states in the column was attained. The onset of resonances was checked by the methods of steady-state and time-resolved photoluminescence. It is shown that, in the case of a resonance, the photoluminescence intensity and the radiative lifetime of excitons increase (up to 0.6-2 ns), while the time of tunneling of charge carriers becomes shorter (shorter than 150 ps). Outside the resonances, tunneling of electrons is appreciably enhanced owing to the involvement of longitudinal optical phonons. If only these phonons are involved, the time of nonresonance tunneling between quantum dots becomes shorter than the time of relaxation of charge carriers from the barrier (100 and 140 ps, respectively)

Authors:
; ; ;  [1];  [2]; ;  [3]; ;  [4]
  1. Fock Institute of Physics at the St. Petersburg State University (Russian Federation)
  2. Max-Born-Institut fuer Nichtlineare Optik und Kurzzeitspektroskopie (Germany)
  3. Max-Planck-Institut fuer Mikrostrukturphysik (Germany)
  4. Russian Academy of Sciences, St. Petersburg Physicotechnical Research and Education Complex (Russian Federation)
Publication Date:
OSTI Identifier:
21088439
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 41; Journal Issue: 2; Other Information: DOI: 10.1134/S1063782607020169; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Ltd; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CHARGE CARRIERS; ELECTRIC FIELDS; GALLIUM ARSENIDES; INDIUM ARSENIDES; LAYERS; MOLECULAR BEAM EPITAXY; P-N JUNCTIONS; PHONONS; PHOTOLUMINESCENCE; QUANTUM DOTS; TRANSMISSION ELECTRON MICROSCOPY; TUNNEL EFFECT

Citation Formats

Talalaev, V. G., E-mail: talalaev@mpi-halle.mpg.de, Novikov, B. V., Sokolov, A. S., Strom, I. V., Tomm, J. W., Zakharov, N. D., Werner, P., Cirlin, G. E., and Tonkikh, A. A. Resonances related to an array of InAs quantum dots and controlled by an external electric field. United States: N. p., 2007. Web. doi:10.1134/S1063782607020169.
Talalaev, V. G., E-mail: talalaev@mpi-halle.mpg.de, Novikov, B. V., Sokolov, A. S., Strom, I. V., Tomm, J. W., Zakharov, N. D., Werner, P., Cirlin, G. E., & Tonkikh, A. A. Resonances related to an array of InAs quantum dots and controlled by an external electric field. United States. doi:10.1134/S1063782607020169.
Talalaev, V. G., E-mail: talalaev@mpi-halle.mpg.de, Novikov, B. V., Sokolov, A. S., Strom, I. V., Tomm, J. W., Zakharov, N. D., Werner, P., Cirlin, G. E., and Tonkikh, A. A. Thu . "Resonances related to an array of InAs quantum dots and controlled by an external electric field". United States. doi:10.1134/S1063782607020169.
@article{osti_21088439,
title = {Resonances related to an array of InAs quantum dots and controlled by an external electric field},
author = {Talalaev, V. G., E-mail: talalaev@mpi-halle.mpg.de and Novikov, B. V. and Sokolov, A. S. and Strom, I. V. and Tomm, J. W. and Zakharov, N. D. and Werner, P. and Cirlin, G. E. and Tonkikh, A. A.},
abstractNote = {Photoluminescence of multilayer structures with InAs quantum dots grown in the p-n junction in GaAs by molecular-beam epitaxy is studied. Formation of vertical columns of quantum dots is verified by the data of transmission electron microscopy. It is shown that a natural increase in the size of quantum dots from layer to layer brings about their vertical coalescence at the upper part of a column. An unbalance of electronic levels caused by the enlargement of quantum dots was compensated by an external electric field, so that the resonance of ground electronic states in the column was attained. The onset of resonances was checked by the methods of steady-state and time-resolved photoluminescence. It is shown that, in the case of a resonance, the photoluminescence intensity and the radiative lifetime of excitons increase (up to 0.6-2 ns), while the time of tunneling of charge carriers becomes shorter (shorter than 150 ps). Outside the resonances, tunneling of electrons is appreciably enhanced owing to the involvement of longitudinal optical phonons. If only these phonons are involved, the time of nonresonance tunneling between quantum dots becomes shorter than the time of relaxation of charge carriers from the barrier (100 and 140 ps, respectively)},
doi = {10.1134/S1063782607020169},
journal = {Semiconductors},
number = 2,
volume = 41,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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