Optical measurement of induced electric field in water using Pockels device

Abstract

The induced toroidal electric field in water was optically measured by means of a Pockels device. For induction of the electric field based on the transformer principle, multiple primary coils have been used in order to avoid the increase in the primary voltage. A Bi/sub 12/SiO/sub 20/ crystal with a relative permittivity of 56 is used as the Pockels device. Since the electric field inside the crystal becomes much smaller than that in air due to the large permittivity, the electric field measurement has been performed in water in order to increase the sensitivity. The retardations by Pockels effect are on the order of 10/sup -3/ approximately 10/sup -2/, and V/cm, which agrees with those calculated from one-turn voltage within about 20%.<>