Langevin Method for Damped Quantum-Mechanical Systems

Abstract

It is shown that the Langevin forces needed to convert expectation-value equations into operator equations for a two-level system cannot be Gaussian, and arguments are presented for extending this result to other nonlinear systems. In order to satisfy quantum-mechanical requirements, a generalization to higher-order moments of a procedure used for specifying second-order moments of the Langevin forces is proposed.