Electro-Optic Characteristics of a Cooled Deuterated Potassium Dihydrogen Phosphate Crystal

The half-wave voltage of a deuterated potassium dihydrogen phosphate (DKDP) crystal was measured between 231 K and room temperature. It was found to decrease linearly with crystal temperature at a rate of 55.1 V/K. The lowest voltage of 511 V was observed at 231 K, which is one eighth of that at room temperature. The cooled DKDP crystal was discussed for use as an electro-optic modulator as it provides various advantages such as the reduced voltage of the power supply needed and the lower B-integral.