Density-dependent electron scattering in photoexcited GaAs in strongly diffusive regime

作者：Mics Zoltan^*; D' Angio Andrea; Jensen Soren A; Bonn Mischa; Turchinovich Dmitry

来源：Applied Physics Letters, 2013, 102(23): 231120.

DOI：10.1063/1.4810756

In a series of systematic optical pump-terahertz probe experiments, we study the density-dependent electron scattering rate in photoexcited GaAs in the regime of strong carrier diffusion. The terahertz frequency-resolved transient sheet conductivity spectra are perfectly described by the Drude model, directly yielding the electron scattering rates. A diffusion model is applied to determine the spatial extent of the photoexcited electron-hole gas at each moment after photoexcitation, yielding the time-dependent electron density, and hence the density-dependent electron scattering time. We find that the electron scattering time decreases from 320 to 60 fs, as the electron density changes from 10(15) to 10(19) cm(-3).

• 出版日期2013-6-10