Journal of Optics B Quantum and Semiclassical Optics

Distinguishing Schrödinger cats in a lossy environment

A. Gábris, Петер Адам, Mátyás Koniorczyk, József Janszky

Published Mar 1, 2004• 7 citations

Abstract

Optical Schrödinger cat states—that is, even and odd coherent states—are considered as possible candidates for forming a computational basis for a coherent state qubit. The distinguishability of the two originally orthogonal states after experiencing loss is quantified in terms of quantum relative entropy. This is a physically instructive quantity related to probabilities of faults in identifying the state. This distinguishability is important for classical communication and for the problem of reading out the result of a quantum computation by a lossy device. It is shown that the distinguishability can significantly increase if the environment is prepared in an appropriately chosen squeezed state.

DOI: 10.1088/1464-4266/6/3/014

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