Effect of radiation defects on electrophysical parameters of layered CuInP2S6 ferrielectrics

Abstract

We have found that irradiation of CuInP2S6 samples with β and γ particles significantly affects the dielectric constant both at the phase transition and at room temperature. Moreover, the phase transition temperature and the shape of the anomaly ε(T) do not change significantly. An increase in the irradiation dose enhances the suppression of the dielectric constant, and the replacement of β with γ particles further reduces ε. This phenomenon is most likely due to an increase in the defectiveness of the crystal structure, and the difference in the efficiency of β and γ particles is caused by the different penetration depths of these particles. The formed radiation defects are most likely charged, which capture charge carriers in the CuInP2S6 crystal, which is manifested in the reduced electrical conductivity of the samples. This behavior can be observed in the form of a decrease in the hightemperature "tails" ε*(T) above 330 K, which are caused by the conductivity of the samples.