Transient reflectivity measurement of photocarrier dynamics in GaSe thin films

• DOI: 10.1007/s00340-017-6677-z
• Publication Date: 2017-03-10T06:58:05Z
• Authors: Xinwu Zhang; Shenwei Wang; Guangmiao Wan; Yanwei Zhang; Miaoling Huang; Lixin Yi
• Keywords: Transient (computer programming); Dynamics; Electron Mobility

We report a spatially, temporally, and spectrally resolved transient reflectivity measurement on photocarrier lifetime and diffusion in GaSe. We directly obtain a carrier lifetime of about 260 ps and a diffusion coefficient of about 5.5 cm2 s−1, both at room temperature. From these quantities, we further deduce a mean free time of about 90 fs, a mean free path of about 6 nm, a diffusion length of about 360 nm, and a mobility of about 190 cm2 V−1 s−1. These results provide fundamental information for understanding carrier dynamics in this material and its applications in electronics and optoelectronics.