A Monte Carlo Method Seamlessly Linking Quantum and Classical Transport Calculations

A Monte Carlo method for carrier transport is presented, which simultaneously takes into account quantum interference and dissipation effects. The method solves the space-dependent Wigner equation including semi-classical scattering through the Boltzmann collision operator. To this equation a particle model is assigned, which interprets the non-local potential operator as a generation term for numerical particles of positive and negative statistical weight. A numerical technique to control the avalanche of numerical particles is discussed. Since the Wigner equation simplifies to the Boltzmann equation in classical device regions, the solutions of the quantum kinetic equation and the classical one are linked in a natural way. This approach allows the simulation of a quantum region embedded in an extended classical region. Results of this approach are demonstrated for a resonant tunneling diode.