细菌视紫红质三阶非线性光感应超快过程研究

PHOTO-INDUCED ULTRAFAST PROCESS OF THIRD-ORDER OPTICAL NONLINEARITY IN BACTERIORHODOPSIN

用前向立体简并四波混频实验对光能转换生物分子细菌视紫红质 ( b R)作三阶非线性光学超快过程研究 ,观察到时间响应由快成份和慢成份组成 .用激子位相空间充满理论和构形变化模型分别给予动力学机制解释 .快成份对应于自由电子 -空穴对形成的激子 ,慢成份对应于无辐射衰变形成的极化子 .通过对实验曲线的数学拟合 ,得到激子饱和密度和激子长度 ,激子和极化子寿命、以及极化子形成效率等动力学参数 .

Photo-induced ultrafast process in bacteriorhodopsin was observed with DFWM technique. The origin of the fast component(ps) and the slow component (ns) in photo-excitation dynamics was explained on the basis of models of both the phase space filling and the conformational deformation. The former is due to the excitons made from free electron-hole pairs and the latter is owing to the polaron induced from the non-radiative decay. The saturation density and length of excitons, the life time of exciton and polaron, and the polaron state formation efficiency were extracted by a least square fitting procedure.