Cu-Ba-O薄膜在超短激光脉冲作用下的光透射率特性

Characteristics of Optical Transmissivity of Cu-Ba-O Thin Filmunder Action of Ultrashort Laser Pulses

用泵浦－探测技术测量了金属－介质复合薄膜Ｃｕ－Ｂａ－Ｏ的光学透射率在超短激光脉冲作用下随延迟时间的瞬态变化曲线，获得了薄膜对光的透射率迅速减小并在皮秒时间内恢复原状的实验结果。该现象是由薄膜中金属超微粒子内费米能级附近电子被飞秒激光脉冲激发所产生的非平衡态电子经历瞬态弛豫造成的。本文从理论上给出了薄膜中Ｃｕ超微粒子的电子声子相互作用常数ｇ的修正数值。

The pumpprobe method was used for measuring the transient change of optical transmissivity of metal particlematrix composite thin film Cu-Ba-O exposed to ultrashort laser pulses. The phenomenon was observed that the optical transmissivity in the thin film rapidly decreased and then recovered in a few picoseconds. The optical relaxation is a process in which nonequilibrium electrons, excited by laser pulses and originating from near Fermi level in Cu ultrafine particles, return to the equilibrium state. An amended theoretical value of electronphonon coupling constant g of Cu ultrafine particles in the composite thin film was given.