Wigner distribution function analysis of a Schrödinger cat superposition of displaced equilibrium coherent states

Motivated by recent experiments, we consider a Schrödinger cat superposition of two widely separated coherent states in thermal equilibrium. The time development of our system is obtained using Wigner distribution functions. In contrast to our discussion for a two-Gaussian wave packet [ Phys. Lett. A 286 (2001) 87]. we find that, in the absence of dissipation, the interference term does not decay rapidly in time, but in common with the other two terms, it oscillates in time and persists for all times.