Electron-phonon interactions in modulation-dopedAlxGa1−xAs/GaAs heterojunctions

The mobilities and energy-loss rates of electrons in modulation-doped ${\mathrm{Al}}_{\mathrm{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathrm{x}}$As/GaAs heterojunctions at low temperatures are theoretically investigated based on the electron-phonon interactions. By using an extended Fang-Howard wave function it is shown that the experimental data on the mobilities and energy-loss rates of electrons are well explained in terms of the deformation-potential constant D=8 eV without screening and the piezoelectric constant P=0.052 with screening. As a result we can conclude that there are no discrepancies between the electron-phonon interactions in the ${\mathrm{Al}}_{\mathrm{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathrm{x}}$As/GaAs heterojunctions and the bulk GaAs.