【摘要】 根据耦合波方程 ,分析了准周期光学超晶格中激光变频过程 ,在倍频过程满足准位相匹配条件 ,和频过程不满足准位相匹配条件与倍频过程不满足准位相匹配条件 ,和频过程满足准位相匹配条件下对不同参量进行了数值模拟 ,结果表明在小信号近似条件下的转换效率依赖于耦合系数比α ,和频位相失配量越大 ,二次谐波的转换效率与三次谐波的转换效率相差越小 ,这不利于产生高效的三倍频。更多还原

【Abstract】 The laser frequency conversion process in quasi periodic optical superlattice is analyzed by use of the couple wave equation.The numerical simulation is conducted with different parameters for the process of second harmonic generation (SHG) under the quasi phase matched (QPM) condition,sum frequency generation (SFG) under the quasi phase mismatched (QPMM) condition,SHG under the QPMM condition and SFG under the QPM condition.The results verify that the conversion efficiency is dependent on the ratio of coupling coefficients α under the assumption of small signal approximation.In addition,the langer the magnitude of phase mismatch of SFG is,the smaller the difference between conversion efficiency of SHG and third harmonic generation (THG) is,this is unfavorable to high efficiency THG.更多还原