Probing the momentum relaxation time of charge carriers in ultrathin semiconductor layers

摘要

We report on a terahertz time-domain technique for measuring the momentumrelaxation time of charge carriers in ultrathin semiconductor layers. The phasesensitive modulation technique directly provides the relaxation time.Time-resolved THz experiments were performed on n-doped GaAs and show preciseagreement with data obtained by electrical characterization. The technique iswell suited for studying novel materials where parameters such as the chargecarriers' effective mass or the carrier density are not known a priori.