High-field electron transport in GaAs/Al xGa 1− xAs p–i–n–i–p-structures investigated by ultrafast absorption changes

Abstract

High-field electron transport is studied in a GaAs/Al x Ga 1− x As p–i–n–i–p-structure with a specially designed composition profile. Electron transfer in real space and energy relaxation is investigated via time-resolved measurements using various probe energies. We observe a transfer time of ∼10 ps for the transport of electrons over 600 nm . This time is found to be nearly independent of the reverse bias voltage. The experimental findings are in good agreement with Monte Carlo simulations.