On convergence of one-step schemes for weak solutions of quantum stochastic differential equations

Several one-step schemes for computing weak solutions of Lipschitzian quantum stochastic differential equations (QSDE) driven by certain operator-valued stochastic processes associated with creation, annihilation and gauge operators of quantum field theory are introduced and studied. This is accomplished within the framework of the Hudson-Parthasarathy formulation of quantum stochastic calculus and subject to the matrix elements of solution being sufficiently differentiable. Results concerning convergence of these schemes in the topology of the locally convex space of solution are presented. It is shown that the Euler-Maruyama scheme,with respect to weak convergence criteria for Ito stochastic differential equation is a special case of Euler schemes in this framework. Numerical examples are given.