时间延迟激光感生双光栅的理论及实验研究

Theoretical and experimental study of the time-delayed laser-induced double gratings

从理论上分析了激光相位及振幅的随机涨落对由热效应引起的时间延迟激光感生双光栅(TDLIDG)的影响.结果表明,四波混频信号调制的振幅随两束泵光相对延迟的增加而衰变.实验结果与理论预测基本一致.我们还证实用TDLIDG测量两束光的波长差可以达到与激光线宽同一量级的精度.

The effect of phase and amplitude fluctuation of lasers on the time-delayed laser-induced double gratings (TDLIDG) caused by thermal effect has been analysed theoretically in this paper. It is found that the modulation amplitude of four-wave mixing signal decays as the relative time delay between two pump beams increases. Experimental results agree quite well with the theoretical predication. We also demonstrated that, when TDLIDG was employed for the wavelength difference measurement, the accuracy could reach the same order of magnitude as the laser linewidth.