Ferroelectric phase transition and impurity-lattice correlations in Pb1-XGeXTe(Ga)

Abstract

The impedance of single-crystal samples of PbTe(Ga) and Pb1-XGeXTe(Ga) (0≤x≤0.095) is investigated in the frequency range from 102 to 106 Hz and temperature range 4.2–300 K. The temperature dependence of the capacitance of all the Pb1-XGeXTe(Ga) samples studied exhibited two types of features. These are a pronounced peak at a temperature T ~ Tph, caused by a dielectric anomaly at the ferroelectric phase transition, and strong frequency dependent increase of the capacitance in the temperature region T