V. Kalinin et L. Solymar, The influence of surface states and light attenuation on transient phenomena in photorefractive films, J OPT A-P A, 2(5), 2000, pp. 405-410
The distribution of free electrons and the formation of the electric field
from the dark condition are analysed in an insulator-photorefractive (PR) f
ilm-insulator sandwich illuminated by a single optical beam in the absence
of an external electric field. Boundary conditions are derived that take in
to account the dynamics of fast surface states. The mathematical solution f
or the transient process is obtained, based on the well known transport equ
ations of photorefractive theory. The role of surface states and attenuatio
n is discussed. In particular, it is shown that the character of transients
in the boundary depletion layers depends on the ratio of the charged surfa
ce state lifetime to the dielectric relaxation time. It is also shown that
the width of the depletion layers varies with time if the diffusion length
differs from the Debye length.