Abstract:
The superconducting properties of Pb$_{0.05}$Sn$_{0.95}$Te semiconductor alloy doped with 5 at % of In are investigated at a hydrostatic pressure of $P<$ 7 kbar. At increasing pressure $P>$ 1.35 kbar and $T\ge$ 1.3 K, the resistivity step to $\rho$ = 0 in the temperature and magnetic-field dependences $\rho(T)$ and $\rho(H)$, which corresponds to the transition to the superconducting state, disappears. The experimental results are indicative of a decrease in the density of states at the Fermi level with increasing pressure, which can be interpreted as an indium-level shift deep into the valence band. The obtained data refine and supplement the results of studies devoted to investigation of the baric dependences of the critical parameters of the superconducting transition in
(Pb$_{z}$Sn$_{1-z}$)$_{0.95}$In$_{0.05}$Te with varying lead content $z$.