Ioffe Physico-Technical Institute RAS, 26 Politekhnicheskaya, St.-Petersburg 194021, Russia
Received Octouber 11, 2018, published online December 20, 2018
Magnetic field dependences of magnetization of semiconducting solid solution (PbzSn1–z)0.84In0.16Te were studied in temperature range 2–300 K and in fields up to 30 kOe. Solutions with highest critical parameters of superconducting transition z = 0.3, 0.4 were chosen. In (Pb0.4Sn0.6)0.84In0.16Te material critical temperature Тс ≈ 3.8 K and critical magnetic field Нс2 = 22 kOe (Т = 2 K). Secondary maximum (or peak-effect) was observed in m(H) dependences at Т < Тс and in fields close to Нс2. Secondary peak height at T = 2 K in z = 0.4 sample is up to 15% of the height of the first maximum, caused by the transition from Meissner state to mixed state. Secondary peak position relative to Hc2 does not change with temperature increase, but its height decreases and at T > 3 K peak-effect can’t be observed. Origins of the peak-effect in (PbzSn1–z)0.84In0.16Te, z = 0.3 и 0.4, is discussed based on obtained data. Models based on analysis of pinning centers system in the material and vortex structure dynamics with changing external parameters are considered.