Journal of Optics B Quantum and Semiclassical Optics

Multiple Schrödinger cat states at finite temperature

Pablo Barberis, Shahen Hacyan

Published May 11, 2000• 3 citations

Abstract

A multiple Schrödinger cat state can be defined as a quantum superposition of an arbitrary number of coherent states. In this paper, we study the process of decoherence of such multiple states in interaction with their environments, using the model of a harmonic oscillator coupled to a thermal bath. The evolution of a superposition of various coherent states into a statistical mixture is described with the Wigner distribution function. The decoherence effect is expressed in analytic form, and it is seen that the damping time is very sensitive to the temperature. Multiple superpositions of states can be conveniently described using crystallographic group techniques; numerical calculations of the Wigner functions for some typical groups are also presented.

DOI: 10.1088/1464-4266/2/3/303

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