Polarization reversal in KTiOPO4 crystals

Characteristics of spontaneous polarization reversal have been studied in detail for the first time in KTiOPO4 crystals subjected to a pulsed electric field in the range 15-70 kV cm(-1). The switching process has been observed by recording a transient switching current and subsequent piezoelectric probe mapping and optical and secondary electron microscopy methods. The measured value of spontaneous polarization is 20.1 mu C cm(-2). The ionic potassium DC current was observed to have a strong effect on the polarization switching. The developed experimental set-up has made it possible to fabricate a periodic domain structure and to generate an optical second harmonic power.