Effects of interface-roughness scattering on nonlinear electron transport in a superlattice based on exact solution of generalized Boltzmann transport equation

In this paper, an effective scattering-potential approach is proposed for treating interface-roughness scattering of drifting electrons within a superlattice. By utilizing established effective scattering potentials, a quasi-one-dimensional generalized Boltzmann transport equation is developed after a self-consistent internal scattering force is included. This generalized Boltzmann transport equation is solved exactly afterwords beyond the relaxation-time approximation. Furthermore, the dependence of the resulting steady-state current on interface-roughness parameters is analyzed at various temperatures and dc electric-field strengths by utilizing the calculated nonequilibrium electron occupation function. Meanwhile, the microscopic mechanism behind non-ohmic transport behavior is revealed by analyzing numerically the computed nonequilibrium electron occupation function and its dependence on interface roughness parameters as well as the dc electric field strength.