Reversal of subpicosecond carrier transport direction with temperature observed in semi-insulating InP using THz radiation

Abstract The temperature dependence of the subpicosecond carrier transport in SI-InP has been studied in detail using the THz radiation between 20 and 300 K. It is found that the phase reversal of the waveform occurs at ∼120 K. The reversal indicates the change of the carrier transport direction and is discussed on the basis of the drift-diffusion model.