增益介质中Compton散射对小尺度自聚焦的影响

通过对激光放大介质中多光子非线性Compton散射光小尺度自聚焦特性的研究,提出了小尺度自聚焦的非线性理论,并对小尺度调制方程、增益谱和成丝距离进行了修正.研究发现:散射光的临界频率和最快增长频率近乎是相同的,在介质增益下,散射光引起的非线性扰动最快增长频率和最大增长率与背景光强度和传输距离几乎无关.在一定输入和输出功率下,在散射光出现的初始阶段,它使背景光的能量、小尺度扰动最快增长频率、最大增益和相应的B积分迅速增大,调制谱的范围迅速加宽,成丝距离延长;之后,它们的变化几乎与散射光无关.

Influences of Compton scattering on the small-scale self-focusing in the gain medium

According to the properties of the small-scale self-focusing of the multi-photon nonlinear Compton scattering in gain medium,the theory of the nonlinear scattering of the small-scale self-focusing was put forward,and the small-scale modulation equation,gain rela- tion and filamentation distance were revealed.The results show that the critical frequency and the fastest growing frequency are almost the same.In the gain medium,the fastest growing frequencies of the nonlinear disturbance and the largest rate of rise taken place by Compton scattering almost have not relations with the background optical intensity and propagation distance.Under the certain input and output powers,in the initial stage of the scattering,the background optical energy,the fastest growing frequency of the small-scale disturbance,the largest gain and its B integral are quickly increased,the scope of the modulating frequency is quickly widened,and the filamentation distance is prolonged by the scattering optical.Then, their changes almost have not relations with the scattering.