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Title: Optical studies of carriers’ vertical transport in the alternately-strained ZnS{sub 0.4}Se{sub 0.6}/CdSe superlattice

Abstract

We present the results of theoretical modelling and experimental optical studies of the alternatively-strained CdSe/ZnS{sub y}Se{sub 1−y} (y = 0.4) superlattice (SL) with effective band-gap E{sub g}{sup eff} ∼ 2.580 eV and a thickness of ∼300 nm, which was grown by molecular-beam epitaxy on a GaAs substrate. The thicknesses and composition of the layers of the superlattice are determined on the basis of the SL minibands parameters calculated implying both full lattice matching of the SL as a whole to a GaAs substrate and high efficiency of photoexcited carriers transport along the growth axis. Photoluminescence studies of the transport properties of the structure (including a superlattice with one enlarged quantum well) show that the characteristic time of the diffusion of charge carriers at 300 K is shorter than the times defined by recombination processes. Such superlattices seem to be promising for the formation of a wide-gap photoactive region in a multijunction solar cell, which includes both III–V and II–VI compounds.

Authors:
; ; ; ; ; ;  [1]
  1. Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)
Publication Date:
OSTI Identifier:
22470047
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 49; Journal Issue: 3; Other Information: Copyright (c) 2015 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CADMIUM SELENIDES; CHARGE CARRIERS; DIFFUSION; ENERGY GAP; EV RANGE; GALLIUM ARSENIDES; MOLECULAR BEAM EPITAXY; PHOTOLUMINESCENCE; QUANTUM WELLS; RECOMBINATION; SOLAR CELLS; STRAINS; SUBSTRATES; SUPERLATTICES; ZINC SULFIDES

Citation Formats

Evropeytsev, E. A., E-mail: evropeitsev@beam.ioffe.ru, Sorokin, S. V., Gronin, S. V., Sedova, I. V., Klimko, G. V., Ivanov, S. V., and Toropov, A. A.. Optical studies of carriers’ vertical transport in the alternately-strained ZnS{sub 0.4}Se{sub 0.6}/CdSe superlattice. United States: N. p., 2015. Web. doi:10.1134/S1063782615030070.
Evropeytsev, E. A., E-mail: evropeitsev@beam.ioffe.ru, Sorokin, S. V., Gronin, S. V., Sedova, I. V., Klimko, G. V., Ivanov, S. V., & Toropov, A. A.. Optical studies of carriers’ vertical transport in the alternately-strained ZnS{sub 0.4}Se{sub 0.6}/CdSe superlattice. United States. doi:10.1134/S1063782615030070.
Evropeytsev, E. A., E-mail: evropeitsev@beam.ioffe.ru, Sorokin, S. V., Gronin, S. V., Sedova, I. V., Klimko, G. V., Ivanov, S. V., and Toropov, A. A.. Sun . "Optical studies of carriers’ vertical transport in the alternately-strained ZnS{sub 0.4}Se{sub 0.6}/CdSe superlattice". United States. doi:10.1134/S1063782615030070.
@article{osti_22470047,
title = {Optical studies of carriers’ vertical transport in the alternately-strained ZnS{sub 0.4}Se{sub 0.6}/CdSe superlattice},
author = {Evropeytsev, E. A., E-mail: evropeitsev@beam.ioffe.ru and Sorokin, S. V. and Gronin, S. V. and Sedova, I. V. and Klimko, G. V. and Ivanov, S. V. and Toropov, A. A.},
abstractNote = {We present the results of theoretical modelling and experimental optical studies of the alternatively-strained CdSe/ZnS{sub y}Se{sub 1−y} (y = 0.4) superlattice (SL) with effective band-gap E{sub g}{sup eff} ∼ 2.580 eV and a thickness of ∼300 nm, which was grown by molecular-beam epitaxy on a GaAs substrate. The thicknesses and composition of the layers of the superlattice are determined on the basis of the SL minibands parameters calculated implying both full lattice matching of the SL as a whole to a GaAs substrate and high efficiency of photoexcited carriers transport along the growth axis. Photoluminescence studies of the transport properties of the structure (including a superlattice with one enlarged quantum well) show that the characteristic time of the diffusion of charge carriers at 300 K is shorter than the times defined by recombination processes. Such superlattices seem to be promising for the formation of a wide-gap photoactive region in a multijunction solar cell, which includes both III–V and II–VI compounds.},
doi = {10.1134/S1063782615030070},
journal = {Semiconductors},
number = 3,
volume = 49,
place = {United States},
year = {Sun Mar 15 00:00:00 EDT 2015},
month = {Sun Mar 15 00:00:00 EDT 2015}
}
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