Entropy Squeezing in Coupled Field-Superconducting Charge Qubitwith Intrinsic Decoherence

Abstract

We investigate the entropy squeezing in the system of asuperconducting charge qubit coupled to a single mode field. We find anexact solution of the Milburn equation for the system and discuss theinfluence of intrinsic decoherence on entropy squeezing. As a comparison, wealso consider the variance squeezing. Our results show thatin the absence ofthe intrinsic decoherence both entropy and variance squeezings have the sameperiodic properties of time, and occur at the same range of time. However,when the intrinsic decoherence is considered, we find that as the timegoing on the entropy squeezing disappears fast than the variance squeezing,there exists a range of time where entropy squeezing can occur butvariance squeezing cannot.