KNSBN crystals were grown successfully with both Cu & Ce dopings. Two-wave
mixing experiments and light-induced absorption changes experiments in (Cu,
Ce):KNSBN crystals were carried out. The two-wave coupling gain was measure
d to be as large as 10cm(-1). (Cu,Ce):KNSBN exhibits strong intensity and p
olarization-dependent absorptions at red wavelength. Light-induced absorpti
on coefficients of up to 0. 53cm(-1) and 0. 26cm(-1) were obtained using an
Ar laser pump beam for the extraordinary and ordinary probe beams, respect
ively. The results indicate that the two-center charge transport model is m
ore appropriate for KNSBN.