Transient carrier velocities in bulk GaAs: Quantitative comparison between terahertz data and ensemble Monte Carlo calculations

Abstract

Transient carrier velocities determined from terahertz radiation emitted from photoexcited bulk GaAs have been compared with ensemble Monte Carlo calculations. It is found that, if actual experimental conditions (sample geometry, photoexcitation condition, etc.) are properly taken into account, Monte Carlo calculations give a very good description of the transient carrier velocities determined from THz measurements. Although the THz signal is dominated by electron transport, contribution of holes becomes appreciable when the electric field is higher than 20 kV/cm.