Simulation of Decoherence by Averaged Semiquantum Method for Spin-Boson Model

We investigate the dynamics of a system coupled to an environment by averaged semiquantum method.The theory origins from the time-dependent variational principle（TDVP）formulation and contains nondiagonal matrixelements.So it can be applied to study dissipation,measurement,and decoherence problems in the model（H=h;+h;+h;）.In the calculation,the influence of the environment govern by differential dynamical equation is incorporatedthrough a mean Geld.We have performed averaged semiquantum method for a spin-boson model,which reproduce theresults from stochastic Schrodinger equation method and Hierarchical approach quite accurately.The problems,dynamicsin nonequilibrium environments,have also been studied by our method.