The dynamic behavior of the complementary space-charge gratings formed in a Bi12SiO20 crystal through prolonged recording at 780 nm is used to determine a number of significant photorefractive parameters, including effective trap density, diffusion length, and dielectric relaxation time, simultaneously for both types of charge carriers. This simple, all-optical method does not require prior knowledge of any other photorefractive parameters and therefore represents the only procedure currently available capable of direct materials evaluation in the low-coupling regime. Furthermore, the scheme provides the means for quantitatively assessing the effects of crystal sensitization resulting, for example, from uniform preillumination.
© 1998 Optical Society of America
L. Boutsikaris, S. Mailis, and N. A. Vainos, "Determination of the photorefractive parameters of Bi12SiO20 by study of the dynamic behavior of complementary gratings," J. Opt. Soc. Am. B 15, 1042-1051 (1998)