A. Grunnetjepsen et al., INVESTIGATION OF THE INTERNAL FIELD IN PHOTOREFRACTIVE MATERIALS AND MEASUREMENT OF THE EFFECTIVE ELECTROOPTIC COEFFICIENT, Journal of the Optical Society of America. B, Optical physics, 12(5), 1995, pp. 921-929
An experimental investigation of the electric field in the bulk of a B
i12SiO20 crystal is carried out, and a two-region model is developed t
hat can account for the buildup of screening charges near the electrod
es. In light of our results, a simple method is proposed for the deter
mination of the effective electro-optic coefficients based on applying
a sufficiently high-frequency square-wave voltage to prevent screenin
g charge buildup. A demonstration of this method for Bi12SiO20 leads t
o a value of 4.4 pm/V for the stress-free (unclamped) coefficient, and
a subsequent consideration of piezoelastic contributions allows the s
train-free (clamped) coefficient to be estimated at 3.7 pm/V.