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Title: Dielectric properties of polycrystalline ZnS

Abstract

The temperature and frequency dependences of the permittivity of polycrystalline zinc sulfide are investigated. The permittivity is calculated from the electronic-structure parameters. It is shown that an increase in the permittivity at frequencies below 10 kHz occurs as a result of space-charge polarization, which is due to the presence of charged dislocations in interlayer and grain boundaries.

Authors:
;  [1]
  1. Nizhni Novgorod State University (Russian Federation)
Publication Date:
OSTI Identifier:
21088618
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 40; Journal Issue: 1; Other Information: DOI: 10.1134/S1063782606010040; 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; DISLOCATIONS; ELECTRONIC STRUCTURE; FREQUENCY DEPENDENCE; GRAIN BOUNDARIES; KHZ RANGE 01-100; PERMITTIVITY; POLARIZATION; POLYCRYSTALS; ZINC SULFIDES

Citation Formats

Shevarenkov, D. N., E-mail: Shevarenkov@phys.unn.ru, and Shchurov, A. F. Dielectric properties of polycrystalline ZnS. United States: N. p., 2006. Web. doi:10.1134/S1063782606010040.
Shevarenkov, D. N., E-mail: Shevarenkov@phys.unn.ru, & Shchurov, A. F. Dielectric properties of polycrystalline ZnS. United States. doi:10.1134/S1063782606010040.
Shevarenkov, D. N., E-mail: Shevarenkov@phys.unn.ru, and Shchurov, A. F. Sun . "Dielectric properties of polycrystalline ZnS". United States. doi:10.1134/S1063782606010040.
@article{osti_21088618,
title = {Dielectric properties of polycrystalline ZnS},
author = {Shevarenkov, D. N., E-mail: Shevarenkov@phys.unn.ru and Shchurov, A. F.},
abstractNote = {The temperature and frequency dependences of the permittivity of polycrystalline zinc sulfide are investigated. The permittivity is calculated from the electronic-structure parameters. It is shown that an increase in the permittivity at frequencies below 10 kHz occurs as a result of space-charge polarization, which is due to the presence of charged dislocations in interlayer and grain boundaries.},
doi = {10.1134/S1063782606010040},
journal = {Semiconductors},
number = 1,
volume = 40,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
  • The physical properties of polycrystalline ZnS have been thoroughly investigated because luminophores operating in the visible part of the spectrum are mostly ZnS-based. The traditional methods of producing ZnS are quite complicated and laborious. Therefore, the development of new methods is an important and urgent problem. Self-propagating high-temperature synthesis (SHS) is a promising method with rather simple technology and quite low power consumption. The work deals with determination of conditions under which stationary combustion waves propagate in a mixture of Zn and S powders and the problem of producing polycrystalline ZnS activated by dopants introduced in the original mixture. Itmore » should be noted that the properties of synthesized materials depend on the method used in their production. For example, ZnS produced by SHS and activated with Mn exhibits photoluminescent, cathodoluminescent, and X-ray-luminescent properties along with strong triboluminescence that can be used to record strains and in the construction of indicators of pressure variation. It is also worth noting that the industry of luminophores deals with ZnS powders whereas synthesized specimens are monolithic. In the present work, we use acoustic methods to investigate mechanical properties of ZnS-Mn produced by SHS.« less
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  • The dielectric properties of (Ta{sub 2}O{sub 5}){sub 1{minus}x}(BN){sub x} polycrystalline ceramics are reported for 0.0 < x < 0.25. Measurements were made at 1 MHz and temperatures between 0 and 100 C. The dielectric constant is moderately enhanced in the high temperature tantalum oxide phase at low BN concentrations; it then decreases to an essentially composition-independent value at higher concentrations where the low temperature form of tantalum oxide is stabilized. In the low temperature form, above x = 0.05, there is a significant decrease in the temperature coefficient of the dielectric constant with increasing BN content.
  • Irradiation of polycrystals by large thermal neutron fluxes produced large Frenkel-type defects, especially in elements with large effective cross sections for slow neutron capture. It is postulated that the defects create polarization relaxation which increases dielectric losses and polarization when dielectric penetrability before irradiation is not too high (magnesium and zinc titanates). (R. V.J.)
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