Clement A E, Gilbreath G C
Appl Opt. 1991 Jun 20;30(18):2458-64. doi: 10.1364/AO.30.002458.
Photorefractive gain is measured in poled 1% tantalum-doped potassium niobate (KNbO(3)). Two-wave mixing experiments are presented which exploit the r(42) coefficient of KNbO(3) by employing nonsymmetric geometries which rotate the grating vector away from the optic axis. The effect of this rotation on the exponential gain coefficient is shown. Experimental results are compared to an analytic expression derived for this parameter. The experiments were performed using an argon laser stabilized at lambda = 514.5 nm. The light was extraordinarily polarized, and the beams were incident on the b-face of the crystal. The absorption and the response time of the crystal were measured. Losses due to scattering and phase conjugation were also investigated.
光折变增益是在极化的1%钽掺杂铌酸钾（KNbO₃）中测量的。本文展示了双波混频实验，该实验通过采用非对称几何结构使光栅矢量远离光轴，从而利用了KNbO₃的r₄₂系数。展示了这种旋转对指数增益系数的影响。实验结果与针对该参数推导的解析表达式进行了比较。实验使用稳定在λ = 514.5 nm的氩激光进行。光为异常偏振，光束入射到晶体的b面上。测量了晶体的吸收和响应时间。还研究了散射和相位共轭引起的损耗。
