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Title: The band structure and the double metal-insulator-metal phase transition in the conductivity of elastically strained zero-gap Cd{sub x}Hg{sub 1-x}Te

Abstract

In the zero-gap Cd{sub x}Hg{sub 1-x}Te semiconductor subjected to an axial elastic strain, a band gap is formed between the bottom of the conduction band and the top of the valence band. In the new state, the band structure is found to depend on the initial arrangement of the valence subbands, i.e., on the composition defined by the parameter x. At x < 0.135-0.140, the material becomes a semiconductor with an indirect band gap. If 0.140 < x < 160, the band of light holes at k = 0, {gamma}{sub 6}, is found to be above the {gamma}{sub 8} band. As a result, the material becomes a direct-gap semiconductor, and a double 'metal-semiconductor-metal' phase transition in conductivity occurs. In this case, as the strain is increased, the type of conductivity of the zero-gap semiconductor at low temperatures changes according to the sequence as follows: electron metallic conductivity-electron activation conductivity-hopping conductivity-hole metallic conductivity.

Authors:
; ; ;  [1]
  1. National Academy of Sciences of Ukraine, Lashkarev Institute of Semiconductor Physics (Ukraine)
Publication Date:
OSTI Identifier:
21088107
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 41; Journal Issue: 3; Other Information: DOI: 10.1134/S1063782607030049; 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; CADMIUM COMPOUNDS; MERCURY COMPOUNDS; PHASE TRANSFORMATIONS; SEMICONDUCTOR MATERIALS; STRAINS; TELLURIDES

Citation Formats

Venger, E. F., Gasan-zade, S. G., E-mail: gassan@isp.kiev.ua, Strikha, M. V., and Shepelskii, G. A.. The band structure and the double metal-insulator-metal phase transition in the conductivity of elastically strained zero-gap Cd{sub x}Hg{sub 1-x}Te. United States: N. p., 2007. Web. doi:10.1134/S1063782607030049.
Venger, E. F., Gasan-zade, S. G., E-mail: gassan@isp.kiev.ua, Strikha, M. V., & Shepelskii, G. A.. The band structure and the double metal-insulator-metal phase transition in the conductivity of elastically strained zero-gap Cd{sub x}Hg{sub 1-x}Te. United States. doi:10.1134/S1063782607030049.
Venger, E. F., Gasan-zade, S. G., E-mail: gassan@isp.kiev.ua, Strikha, M. V., and Shepelskii, G. A.. Thu . "The band structure and the double metal-insulator-metal phase transition in the conductivity of elastically strained zero-gap Cd{sub x}Hg{sub 1-x}Te". United States. doi:10.1134/S1063782607030049.
@article{osti_21088107,
title = {The band structure and the double metal-insulator-metal phase transition in the conductivity of elastically strained zero-gap Cd{sub x}Hg{sub 1-x}Te},
author = {Venger, E. F. and Gasan-zade, S. G., E-mail: gassan@isp.kiev.ua and Strikha, M. V. and Shepelskii, G. A.},
abstractNote = {In the zero-gap Cd{sub x}Hg{sub 1-x}Te semiconductor subjected to an axial elastic strain, a band gap is formed between the bottom of the conduction band and the top of the valence band. In the new state, the band structure is found to depend on the initial arrangement of the valence subbands, i.e., on the composition defined by the parameter x. At x < 0.135-0.140, the material becomes a semiconductor with an indirect band gap. If 0.140 < x < 160, the band of light holes at k = 0, {gamma}{sub 6}, is found to be above the {gamma}{sub 8} band. As a result, the material becomes a direct-gap semiconductor, and a double 'metal-semiconductor-metal' phase transition in conductivity occurs. In this case, as the strain is increased, the type of conductivity of the zero-gap semiconductor at low temperatures changes according to the sequence as follows: electron metallic conductivity-electron activation conductivity-hopping conductivity-hole metallic conductivity.},
doi = {10.1134/S1063782607030049},
journal = {Semiconductors},
number = 3,
volume = 41,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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  • Photoluminescence (PL) spectra and kinetics of narrow gap Hg{sub 1−x}Cd{sub x}Te/Cd{sub y}Hg{sub 1−y}Te quantum well (QW) heterostructures grown by molecular beam epitaxy technique are studied. Interband PL spectra are observed from 18 K up to the room temperature. Time resolved studies reveal an additional PL line with slow kinetics (7 μs at 18 K) related to deep defect states in barrier layers. These states act as traps counteracting carrier injection into QWs. The decay time of PL signal from QW layers is about 5 μs showing that gain can be achieved at wavelengths 10–20 μm by placing such QWs in HgCdTe structures with waveguides.
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