ac transport of one-dimensional hot electrons in GaAs and ${\mathrm{In}}_{0.53}$${\mathrm{Ga}}_{0.47}$As quantum-well wires at low temperatures

Small-signal ac mobility of hot electrons moving one dimensionally in GaAs and (In,Ga)As quantum-well wires (QWW’s) is studied at lattice temperatures 4.2 and 8 K in the framework of a heated drifted Fermi-Dirac distribution function. The regime where carrier energy loss occurs via deformation potential and piezoelectric couplings to nonequipartitioned acoustic phonons and momentum loss predominantly via background impurity scattering for GaAs QWW’s and alloy scattering for (In,Ga)As QWW’s is considered. Results are calculated for different carrier concentrations and side lengths of the square cross sections of the wires. Cutoff frequencies around 50 and 250 GHz are obtained for GaAs and (In,Ga)As QWW’s, respectively.