Stochastic Simulation of Dissipative Spin Systems

Peter Rabl
I will discuss an efficient numerical method for simulating the dynamics of interacting spin ensembles in the presence of dephasing and decay. The method builds on the discrete truncated Wigner approximation for isolated systems, but is generalized for dissipative spin systems by replacing the deterministic mean-field evolution by a stochastic process that preserves the length of each spin. This technique can be applied for simulating nonclassical spin-squeezing effects or the dynamics and steady states of cavity QED models with hundred thousand interacting two-level systems and without relying on any symmetries. This opens up the possibility to perform accurate real-scale simulations of a diverse range of experiments in quantum optics
or with solid-state spin ensembles under realistic laboratory conditions.