Comparative study of cubic crystals performance in bulk electro-optic sensor for DC and extra-low-frequency measurements

摘要

An electric field sensor based on the linear electro-optic effect is described and the performances of available electro-optic cubic crystals are compared. The sensor sensitivity to an electric field is characterized by a new figure of merit evaluated using crystal data available. The intensity of electric field in the crystal is estimated using the approximation of the rectangular crystal shape by an ellipsoid of revolution. Crystal geometries appropriate for sensors with transverse and longitudinal electro-optic effects are suggested. Influence of the crystal conductivity and the photoconductivity on the sensor performance are investigated. These effects are found to influence the sensor performance if it is used for the dc and extra low frequency electric field measurements.