Experimental study of the time-resolved reflectivity of chromium film

作     者：武腾飞 周常河 戴恩文 谢金 

作者机构：Information Optics Laboratory State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences 

出 版 物：《Chinese Optics Letters》 (中国光学快报（英文版）)

年 卷 期：2009年第7卷第7期

页      面：653-655页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China (No. 60878035) the Shanghai Science and Technology Committee (No.07SA14) the National "973" Program of China (No.2006CB806000) 

主　　题：Chromium Computer simulation Electron electron interactions Electrons Metal recovery Metallic films Phonons Pumping (laser) Pumps 

摘      要：The transient time-resolved reflectivity of chromium film is studied by femtosecond pump-probe technique with a 70-fs laser. Experimental results show that the reflectivity change increases with the power of the pump laser. The fast decrease of the reflectivity occurs between 0-200 fs which is mainly due to the electron-electron interaction. Subsequencely, the slower recovery of the reflectivity between 200-900 fs is mainly due to the electron-phonon coupling process. The reflectivity after 900 fs rises little to a near-constant value for the thermal equilibrium of the system. The experimental results can be explained properly with numerical simulation of the two-temperature model. It is helpful for understanding of the electron ultrafast dynamics in chromium film.