自泵浦相位共轭产生机制和稳定性随入射光波长的变化

Transformation of Mechanism and Stability of Self pumped Phase Conjugation with Wavelengths

当泵浦光波长从５１４．５ｎｍ改变到４８８ｎｍ时，一种掺Ｃｕ的ＫＮＳＢＮ晶体中的自泵浦相位共轭产生机制，从两个相互作用区的猫型机制转变到受激后向散射加四波混频的一个相互作用区机制。４８８ｎｍ的相位共轭光从开始的慢起伏逐渐过渡到准稳状态，而５１４．５ｎｍ的相位共轭光则一直处于无规的不稳定状态。

In a Cu∶KNSBN crystal, the self pumped phase conjugation changes from the cat′s mechanism to stimulated backscattering and four wave mixing mechanism as wavelength of the pump beam being changed from 514.5 to 488 nm. After it is formed, the self pumped phase conjugation at 488 nm changes from slow fluctuation to a quasi sable state gradually in about 400 seconds, while the phase conjugation at 514.5 nm is always in an irregular flutuation state.