Ferroelectric polarization reversal in potassium dideuterium phosphate as monitored by switching current

Ferroelectric polarization reversal in KD2PO4 was monitored using the switching current technique. Switching curves were recorded at temperatures of 169 K to 206 K and at different fields from 54 V/cm to 3300 V/cm. The experimental data were fit to an equation based on the Johnson-Mehl-Avrami model. A comparison was made to work previously carried out by the authors on KH2PO4. The characteristic time increased with decreasing E and decreasing T from 10 μs for 1 kV/cm at 206.5 K to 200 μs for 0.2 kV/cm at 194 K. The effective domain growth dimension increases from 1 at low fields (0.2 kV/cm) to 2.2 at high fields (1.7 to 3 kV/cm). Higher temperatures (203.5, 206.5 K) give higher effective dimensions for electric fields below 1.2 kV/cm. The polarization at 194 K grows from 2 μC/cm2 for 0.2 kV/cm to a saturation value of 4.3 μC/cm2 above 2.5 kV/cm.