损耗对屏蔽光伏空间孤子演化特性的影响

THE IMPACT OF THE LOSS ON THE EVOLUTION OF SCREENING-PHOTOVOLTAIC SPATIAL SOLITONS 

研究了晶体损耗对屏蔽光伏空间孤子在加偏压的光伏光折变晶体中演化特性的影响 .结果表明 ,损耗除了造成屏蔽光伏孤子光波振幅的减小外 ,还造成了孤子横截面的改变 .对于明孤子 ,当入射波光强较低时 ,横截面随传播距离的增长而不断增大 ;而当入射波光强较高时 ,起初横截面不断压缩 ,而后再膨胀 ,并在某一传播距离上孤子横截面恢复到入射时的尺寸 .对于暗孤子 ,不论入射光孤子光强的高低 ,横截面都随传播距离的增长而不断增大 .虽然在传播距离足够短时 ,可以不考虑损耗的影响 ,但距离较大时 ,损耗将最终导致孤子崩溃 .

The impact of linear loss on the evolution of screening-photovoltaic (SP) spatial solitons in biased photovoltaic-photorefractive crystals is investigated. Our numerical study indicates that the loss not only results in the decrease of the amplitude of the soliton beam,but also results in the change of the shape of the soliton beam. For the bright SP soliton,the soliton width increases as the propagation distance increases for the SP soliton with low-intensity at the input,whereas the soliton width decreases initially and then increases as the propagation distance increases, and there is a propagation distance in which the soliton width returns to its value at the input for the SP soliton with high-intensity at the input. For the dark SP soliton,the soliton width increases as the propagation distance increases whether the SP soliton has low- or high-intensity at the input. Though the effect of loss on the evolution of SP soliton can be ignored if the propagation distance is shea enough,the loss is eventually expected to destroy these solitons at long distance.