两色超短脉冲激光与级联三能级分子体系相互作用的动力学研究  

Dynamical behavior of two-color ultrashort laser pulses in a cascade three-level molecular system

作　　者：刘纪彩[1] 赵珂[1] 孙玉萍[1] 王传奎[1] 

机构地区：[1]山东师范大学物理与电子科学学院,济南250014

出　　处：《原子与分子物理学报》2006年第5期815-820,共6页Journal of Atomic and Molecular Physics

基　　金：山东省自然科学基金(Y2004A08);高等学校博士学科点专项科研基金(0040445001);中国科学院上海光机所强光光学研究所开放实验室资助

摘　　要：在不采用旋波近似和慢变幅近似的条件下,采用时域有限差分法和预估矫正法求解Maxwell-Bloch方程,对两色2π超短脉冲激光在级联三能级有机分子体系(4,4′—二甲氨基二苯乙烯分子)中传播的动力学过程进行了数值模拟.该有机分子属于一维对称体系,其电子结构和电学参量在密度泛函水平上给出.在低能量范围内,该分子可以简化为三能级体系.我们研究了在不同共振条件下,两色超短脉冲的时空演化特性和三能级体系各个能级粒子数占有率的分布情况.Using the finite-difference time domain technique(FDTD) for the fields and the predictor-corrector method for the material variables,we solve the Maxwell-Bloch equations beyond the slowly-varying envelope approximation and the rotating-wave approximation.4,4′-bis(dimethylamino) stilbene organic molecule is one type of one-dimensional symmetrical system and its electronic structure and parameters are calculated by density functional theory.The molecule can be simplified as a three-level system.By numerically simulating the propagation of two-color 2π ultrashort laser pulses in a cascade three-level organic molecule system,we analyze the temporal-spatial evolution properties of the ultrashort laser pulses and the population of each energy level under different resonant conditions.

关 键 词：超短脉冲激光 麦克斯韦-布洛赫方程 三能级体系 双光子吸收 

分 类 号：O437[机械工程—光学工程] O561.1[理学—光学]