Negative minority-electron mobility in a nonequilibrium electron-hole plasma

The recently observed phenomenon of negative minority-electron mobility in a GaAs-${\mathrm{Al}}_{\mathrm{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathrm{x}}$As heterostructure is investigated theoretically, employing a balance-equation formulation of nonlinear carrier transport with dynamic carrier screening fully incorporated. Minority-electron mobilities limited by dynamically screened electron-hole interactions and phonon scatterings are calculated as functions of the applied electric field and lattice temperature, and are shown to be in good agreement with experimental data. Energy-transfer rates for the minority electrons and the electron and hole carrier temperatures are also calculated in this work.