title: A transmission-grating-modulated pump-probe absorption spectroscopy and demonstration of diffusion dynamics of photoexcited carriers in bulk intrinsic GaAs film.
abstract: A transmission-grating-modulated time-resolved pump-probe absorption spectroscopy is developed and formularized. The spectroscopy combines normal time-resolved pump-probe absorption spectroscopy with a binary transmission grating, is sensitive to the spatiotemporal evolution of photoinjected carriers, and has extensive applicability in the study of diffusion transport dynamics of photoinjected carriers. This spectroscopy has many advantages over reported optical methods to measure diffusion dynamics, such as simple experimental setup and operation, and high detection sensitivity. The measurement of diffusion dynamics is demonstrated on bulk intrinsic GaAs films. A carrier density dependence of carrier diffusion coefficient is obtained and agrees well with reported results.
authors.affiliation: State-Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Chen
authors.forename: Wenfang
authors.initials: W
authors.lastname: Wang
authors.forename: Jianming
authors.initials: J
authors.lastname: Chen
authors.forename: Jinhui
authors.initials: J
authors.lastname: Wen
authors.forename: Tianshu
authors.initials: T
authors.lastname: Lai