The fanning and the two-wave mixing properties of Ce:KNSBN photorefractive fiber have been studied. The fanning exhibits a strong nonlinear dependence on the incident angle, which differs not only from the bulk Ce:KNSBN crystal but also from the reported photorefractive fiber of other materials. The two-wave coupling gain is also strongly pump beam incident-angle dependent, restricted seriously in a narrow incident angle range, which is attributed to the internal reflection from the side-surface and the fanning effect as well. The numerical fitting method is adopted, which shows to be coincident with the experimental data. The photorefractive fibers have potential applications in signal amplification, holographic storage and phase-conjugation, especially incorporation into optical fiber systems.
|