Ce:KNSBN晶体正交偏振写入光两波耦合特性

Characterictic Two-Wave Coupling in a Ce:KNSBN Crystal with Mutually Orthogonally Polarized Writing Beams

研究了Ce :KNSBN晶体在正交偏振光记录条件下体光栅的两波耦合特性 .实验测量了两波耦合增益系数随泵浦光偏振方向与入射面夹角 φ的变化规律 ,当夹角 φ等于 2 0°或 16 0°时 ,光栅具有最大耦合增益系数 .给出了增益系数随夹角 φ变化规律的数值计算结果 .数值计算结果与实验测量结果较好地吻合 .

Two-wave coupling is studied in a Ce:KNSBN photorefractive crystal with mutually orthogonal polarized waves. The two-wave coupling gain coefficient is experimentally measured with respect to the angle φ between the incident plane and the polarization direction of the pump beam. While the angle φ equals to 20°or 160°, the gain coefficient obtains its maximum value. Theoretical calculated result of the coupling gain coefficient as a function of the angle φ is given, which coincides with the experimental data.