Quantum phase-space distributions with compact support

Abstract

Phase-space representations of quantum distributions such as the Wigner function and Kadanoff–Baym Green's functions do not have compact support which leads to difficulties for numerical and perturbative schemes in quantum transport simulations of nano-devices. We demonstrate that a useful complex-valued quantum phase-space distribution with compact support can be constructed. In many practical applications only the real part is required to obtain useful dynamical averages.