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Title: The band structure and photoluminescence in a Ge{sub 0.8}Si{sub 0.2}/Ge{sub 0.1}Si{sub 0.9} superlattice with vertically correlated quantum dots

Abstract

The energy band diagram of the multilayered Ge{sub 0.8}Si{sub 0.2}/Ge{sub 0.1}Si{sub 0.9} heterostructures with vertically correlated quantum dots is analyzed theoretically. With regard to fluctuations of the thickness layer in the columns of quantum dots and to the exciton-phonon coupling, it is shown that the electron states constitute a miniband. The hole wave functions remain localized in the quantum dots. The spectrum of optical transitions calculated for a 20-layered structure at room temperature is in good agreement with the experimental photoluminescence spectrum that involves an intense band at about 1.6 {mu}m. From theoretical considerations and experimental measurements, specific evidence for the miniband in the superlattice is deduced; it is found that the overlap integrals of the wave functions of electrons and holes and the integrated intensity of the photoluminescence band of the Ge quantum dots are described by quadratic functions of the number of the structure periods.

Authors:
 [1];  [2]; ;  [3];  [4]; ;  [5]
  1. Russian Academy of Sciences, Institute for Analytical Instrumentation (Russian Federation), E-mail: sibirVN@mail.ru
  2. St. Petersburg State University, Fock Institute of Physics (Petrodvorets Branch) (Russian Federation)
  3. Russian Academy of Sciences, Institute for Analytical Instrumentation (Russian Federation)
  4. Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)
  5. Max-Planck-Institut fuer Mikrostrukturphysik (Germany)
Publication Date:
OSTI Identifier:
21088589
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 40; Journal Issue: 2; Other Information: DOI: 10.1134/S1063782606020205; Copyright (c) 2006 Nauka/Interperiodica; Article Copyright (c) 2006 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ELECTRONIC STRUCTURE; GERMANIUM COMPOUNDS; PHOTOLUMINESCENCE; QUANTUM DOTS; SILICON COMPOUNDS; SUPERLATTICES; TEMPERATURE RANGE 0273-0400 K; WAVE FUNCTIONS

Citation Formats

Sibirev, N. V., Talalaev, V. G., Tonkikh, A. A., Cirlin, G. E., Dubrovskii, V. G., Zakharov, N. D., and Werner, P.. The band structure and photoluminescence in a Ge{sub 0.8}Si{sub 0.2}/Ge{sub 0.1}Si{sub 0.9} superlattice with vertically correlated quantum dots. United States: N. p., 2006. Web. doi:10.1134/S1063782606020205.
Sibirev, N. V., Talalaev, V. G., Tonkikh, A. A., Cirlin, G. E., Dubrovskii, V. G., Zakharov, N. D., & Werner, P.. The band structure and photoluminescence in a Ge{sub 0.8}Si{sub 0.2}/Ge{sub 0.1}Si{sub 0.9} superlattice with vertically correlated quantum dots. United States. doi:10.1134/S1063782606020205.
Sibirev, N. V., Talalaev, V. G., Tonkikh, A. A., Cirlin, G. E., Dubrovskii, V. G., Zakharov, N. D., and Werner, P.. Wed . "The band structure and photoluminescence in a Ge{sub 0.8}Si{sub 0.2}/Ge{sub 0.1}Si{sub 0.9} superlattice with vertically correlated quantum dots". United States. doi:10.1134/S1063782606020205.
@article{osti_21088589,
title = {The band structure and photoluminescence in a Ge{sub 0.8}Si{sub 0.2}/Ge{sub 0.1}Si{sub 0.9} superlattice with vertically correlated quantum dots},
author = {Sibirev, N. V. and Talalaev, V. G. and Tonkikh, A. A. and Cirlin, G. E. and Dubrovskii, V. G. and Zakharov, N. D. and Werner, P.},
abstractNote = {The energy band diagram of the multilayered Ge{sub 0.8}Si{sub 0.2}/Ge{sub 0.1}Si{sub 0.9} heterostructures with vertically correlated quantum dots is analyzed theoretically. With regard to fluctuations of the thickness layer in the columns of quantum dots and to the exciton-phonon coupling, it is shown that the electron states constitute a miniband. The hole wave functions remain localized in the quantum dots. The spectrum of optical transitions calculated for a 20-layered structure at room temperature is in good agreement with the experimental photoluminescence spectrum that involves an intense band at about 1.6 {mu}m. From theoretical considerations and experimental measurements, specific evidence for the miniband in the superlattice is deduced; it is found that the overlap integrals of the wave functions of electrons and holes and the integrated intensity of the photoluminescence band of the Ge quantum dots are described by quadratic functions of the number of the structure periods.},
doi = {10.1134/S1063782606020205},
journal = {Semiconductors},
number = 2,
volume = 40,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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