中国激光, 1998, 25 (8): 733, 网络出版: 2006-10-18  

飞秒脉冲激光驱动的薄膜中的非平衡态电子弛豫

Nonequilibrium Electron Relaxation in the Thin Film Stimulated by Femtosecond Pulse Laser
作者单位
北京大学电子学系,光纤通信国家重点实验室,北京 100871
摘要
在飞秒脉冲激光的驱动下, 使用泵浦-探测技术测量了复合薄膜Au-Ba-O的瞬态光学透过率随延迟时间的变化曲线, 观察到了薄膜对光的吸收迅速增大并在皮秒时间内恢复原状的现象。该现象是薄膜中 Au超微粒子内费米能级附近电子被飞秒激光脉冲激发, 产生非平衡态电子而经历瞬态弛豫造成的。从理论上给出了复合薄膜中Au超微粒子的电子声子相互作用常数g的数值。
Abstract
The pump-probe method was used for measuring the transient change of optical transmissivity of a composite thin film Au-Ba-O which was stimulated by a femtosecond pulsed laser. A phenomenon was observed that the optical absorption in the thin film rapidly increased and then recovered in a few picoseconds. Optical relaxation is a process in which nonequilibrium electrons, excited by laser pulses and originating from Au ultrafine particles, return to the equilibrium state. In this paper, a theoretical value of the electron-phonon coupling constant g of Au ultrafine particles in the composite thin filim was given.
参考文献

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吴锦雷, 王传敏. 飞秒脉冲激光驱动的薄膜中的非平衡态电子弛豫[J]. 中国激光, 1998, 25(8): 733. 吴锦雷, 王传敏. Nonequilibrium Electron Relaxation in the Thin Film Stimulated by Femtosecond Pulse Laser[J]. Chinese Journal of Lasers, 1998, 25(8): 733.

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