Low Temperature Physics: 41, 112 (2015); https://doi.org/10.1063/1.4908193
Fizika Nizkikh Temperatur: Volume 41, Number 2 (February 2015), p. 147-152    ( to contents , go back )

The high-pressure effect on superconducting transition parameters of In-doped PbzSn1–zTe semiconducting solid solutions

R.V. Parfeniev, V.I. Kozub, G.O. Andrianov, D.V. Shamshur, A.V. Chernyaev, N.Yu. Mikhailin

A.F. Ioffe Physico-Technical Institute RAN, 26 Politekhnicheskaja Str., St.-Petersburg 194021, Russia
E-mail: D.Shamshur@mail.ioffe.ru

S.A. Nemov

Санкт-Петербургский государственный политехнический университет ул. Политехническая, 29, г. Санкт-Петербург, 195251, Россия
pos Анотація:

Received October 13, 2014

Abstract

The influences of comprehensive compression up to 10 kbar and lead content on superconducting and electrical characteristics of semiconducting solid solutions PbzSn1–zTe doped with indium (5 at.%) are studied. Experimental correlations for the pressure dependences under consideration are found out. It is established that at high pressure condition (P = 6.8 kbar) the material with content of lead z = 0.45 displays a threshold increase of superconductivity up to Тс = 1.7 K, which is typical of the z = 0.05 compound at normal pressure. An increase of hydrostatic pressure P > 3 kbar in (Pb0.05Sn0.95)0.95In0.05Te leads to a decrease of Тс below 1 K. The observed features and the bell-shaped dependence Тс(P) for the z = 0.3 compound are explained by the energy shifting of the band of quasilocal states ЕIn and the state stabilized Fermi energy from the L-valence band into the Σ-valence one with a high density of states as was most noticeable for the z = 0.45 compound. A concentration threshold for the Fermi energy leaving the Σ-valence band with increasing content of lead was determined from the Hall effect data at T = 77 K.

PACS: 71.20.Nr Semiconductor compounds;
PACS: 71.28.+d Narrow-band systems; intermediate-valence solids;
PACS: 71.30.+h Metal-insulator transitions and other electronic transitions;
PACS: 71.55.–i Impurity and defect levels;
PACS: 74.62.Dh Effects of crystal defects, doping and substitution;
PACS: 74.62.Fj Effects of pressure.

Key words: semiconductor solid solution, hydrostatic pressure, superconductivity, the critical parameters of the superconducting state.

Published online: December 22, 2014

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