Quasianalytical Simulation of Ultrafast Relaxation of Photoexcited Electrons in a Semiconductor Quantum Well.

摘要

An analytic function approach is proposed for the system of electron and phonon relaxation during an ultrafast process in GaAs-A1(x)Ga(1-x)As heterojunction. Gauss-type energy functions are used to simulate the peaks of nonthermal electrons, while the background electrons are described by a Boltzmann distribution function. The time variations of parameters describing the amplitudes and widths of Gauss-type functions, and the temperature of background electrons, are determined by solution of solving the Boltzmann equation with electron-electron and electron-phonon interactions. Our choice of analytic distribution function made the calculation simple: only one integral over a two-dimensional momentum q need be numerically handled. After carrier carrier thermalization, our results automatically reduce to that of the electron-temperature model. Keywords: Heterojunction; Gauss type energy; Boltzmann equation; Electron-electron; Electron-phonon; Carrier-carrier; Reprints. (RH)