Quantum dynamics in classical thermal baths Original Research Article

A particular type of open quantum system dynamics is achieved by embedding a quantum system in a classical thermal bath. Such a bath can be represented in terms of the non-Hamiltonian evolution of few variables by means of the so-called Nosè–Hoover Power thermostat. The classical dynamics of the thermostat is integrated by means of time-reversible measure-preserving algorithms. In this work we show that the Nosè–Hoover Power thermostat, when applied to the dissipative evolution of a quantum spin, provides numerical results which agree with those obtained using Nosè–Hoover chains. However, since a fewer number of variables are needed to achieve the correct sampling of the canonical distribution at equilibrium, the Nosè–Hoover Power thermostat promises to be better suited for the simulation of low dimensional open quantum system on discrete grids.