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Title: Terahertz emission from CdHgTe/HgTe quantum wells with an inverted band structure

Abstract

The terahertz electroluminescence from Cd{sub 0.7}Hg{sub 0.3}Te/HgTe quantum wells with an inverted band structure in lateral electric fields is experimentally detected and studied. The emission-spectrum maximum for wells 6.5 and 7 nm wide is near 6 meV which corresponds to interband optical transitions. The emission is explained by state depletion in the valence band and conduction band filling due to Zener tunneling, which is confirmed by power-law current–voltage characteristics.

Authors:
 [1];  [2]; ; ; ;  [1]; ;  [3];  [4]; ; ;  [5]
  1. Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation)
  2. Russian Academy of Sciences, Rzhanov Institute of Semiconductor Physics, Siberian Branch (Russian Federation)
  3. Peter the Great Saint-Petersburg Polytechnic University (Russian Federation)
  4. Ustinov Baltic State Technical University “VOENMEKh” (Russian Federation)
  5. Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)
Publication Date:
OSTI Identifier:
22649741
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 50; Journal Issue: 7; Other Information: Copyright (c) 2016 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CADMIUM COMPOUNDS; ELECTRIC CONDUCTIVITY; ELECTRIC CURRENTS; ELECTRIC FIELDS; ELECTRIC POTENTIAL; ELECTROLUMINESCENCE; ELECTRONIC STRUCTURE; EMISSION SPECTRA; MERCURY TELLURIDES; QUANTUM WELLS; THZ RANGE; TUNNEL EFFECT; VALENCE

Citation Formats

Vasilyev, Yu. B., E-mail: Yu.Vasilyev@mail.ioffe.ru, Mikhailov, N. N., Vasilyeva, G. Yu., Ivánov, Yu. L., Zakhar’in, A. O., Andrianov, A. V., Vorobiev, L. E., Firsov, D. A., Grigoriev, M. N., Antonov, A. V., Ikonnikov, A. V., and Gavrilenko, V. I. Terahertz emission from CdHgTe/HgTe quantum wells with an inverted band structure. United States: N. p., 2016. Web. doi:10.1134/S1063782616070253.
Vasilyev, Yu. B., E-mail: Yu.Vasilyev@mail.ioffe.ru, Mikhailov, N. N., Vasilyeva, G. Yu., Ivánov, Yu. L., Zakhar’in, A. O., Andrianov, A. V., Vorobiev, L. E., Firsov, D. A., Grigoriev, M. N., Antonov, A. V., Ikonnikov, A. V., & Gavrilenko, V. I. Terahertz emission from CdHgTe/HgTe quantum wells with an inverted band structure. United States. doi:10.1134/S1063782616070253.
Vasilyev, Yu. B., E-mail: Yu.Vasilyev@mail.ioffe.ru, Mikhailov, N. N., Vasilyeva, G. Yu., Ivánov, Yu. L., Zakhar’in, A. O., Andrianov, A. V., Vorobiev, L. E., Firsov, D. A., Grigoriev, M. N., Antonov, A. V., Ikonnikov, A. V., and Gavrilenko, V. I. 2016. "Terahertz emission from CdHgTe/HgTe quantum wells with an inverted band structure". United States. doi:10.1134/S1063782616070253.
@article{osti_22649741,
title = {Terahertz emission from CdHgTe/HgTe quantum wells with an inverted band structure},
author = {Vasilyev, Yu. B., E-mail: Yu.Vasilyev@mail.ioffe.ru and Mikhailov, N. N. and Vasilyeva, G. Yu. and Ivánov, Yu. L. and Zakhar’in, A. O. and Andrianov, A. V. and Vorobiev, L. E. and Firsov, D. A. and Grigoriev, M. N. and Antonov, A. V. and Ikonnikov, A. V. and Gavrilenko, V. I.},
abstractNote = {The terahertz electroluminescence from Cd{sub 0.7}Hg{sub 0.3}Te/HgTe quantum wells with an inverted band structure in lateral electric fields is experimentally detected and studied. The emission-spectrum maximum for wells 6.5 and 7 nm wide is near 6 meV which corresponds to interband optical transitions. The emission is explained by state depletion in the valence band and conduction band filling due to Zener tunneling, which is confirmed by power-law current–voltage characteristics.},
doi = {10.1134/S1063782616070253},
journal = {Semiconductors},
number = 7,
volume = 50,
place = {United States},
year = 2016,
month = 7
}
  • Terahertz photoconductivity in magnetic fields in semimetallic HgTe/CdHgTe quantum wells has been studied. The main contribution to photoconductivity comes from a signal that appears as a result of electron-gas heating. It is shown that, with the cyclotron resonance conditions satisfied, the photoconductivity signal is composed of cyclotron-resonance and bolometric components. However, in this case too, the bolometric contribution predominates.
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  • In this study we present measurements of the Terahertz (THz) photoconductivity of 2D electron system realized at HgTe/HgCdTe and AlInSb/InSb/AlInSb quantum wells (QWs) in Corbino geometry (inner and outer radius: 500 {mu}m and 1500 {mu}m) with different mobilities and electron densities. To characterize the devices, the Shubnikov-de Haas (SdH) effect up to magnetic fields B of 7T and current-voltage (I-V) characteristics at various magnetic fields were measured. The THz radiation is provided by a p-Ge laser which operates with a magnetic field and a high voltage for the electrical pumping. The stimulated emission is caused by transitions between Landau levelsmore » of light holes [1]. The laser is tunable in the range between 1.7 to 2.5 THz (corresponding to wavelengths between 120 to 180 {mu}m or energies of 7 to 12 meV). The laser is pulsed with a pulse rate of 1 Hz and pulse lengths of about 1 {mu}s with low switching times (about 20 ns). The monochromatic THz radiation is transferred to our samples via a 0.32m long brass waveguide immersed in liquid Helium. The detection of a change in the conductivity of the sample due to absorption of THz-radiation (photoresponse) requires a low-noise circuit. For the Corbino-shaped samples the photoresponse (PR) is measured via a resistor R{sub V} of 1 k{Omega}. The signal is transferred via in a high-frequency cable and detected with a digital oscilloscope.« less