Anomalous Pyroelectric Properties of SbSI Single Crystals

Abstract

The pyroelectric current in single crystals of SbSI was measured continuously with a d.c. amplifier and a recorder in the temperature range from -170°C to +40°C. The spontaneous polarization was estimated from these measurements. The pyroelectric current in a virgin crystal (free from previous poling treatment) showed several peaks near the Curie point. Optical observation of the crystal carried out simultaneously with the recording of the pyroelectric current revealed that these anomalous peaks corresponded fairly well to the movements of the ferroelectric-paraelectric phase boundaries. The peaks have a tendency to be replaced by a large, main peak when poled with a high d.c. field, and the main peak is again forked into several by irradiation with white light.