Advances in Optics and Photonics

Coherence and entanglement in a two-qubit system

Miguel Orszag, Maritza Hernandez

Published Mar 17, 2010• 36 citations

Abstract

Entanglement is a fundamental concept in quantum mechanics. In this review, we study various aspects of coherence and entanglement, illustrated by several examples. We relate the concepts of loss of coherence and disentanglement, via a model of two two-level atoms in different types of reservoir, including cases of both independent and common baths. Finally, we relate decoherence and disentanglement, by focusing on the sudden death of the entanglement and the dependence of the death time with the distance of our initial condition from the decoherence-free subspace. In particular, we study the sudden death of the entanglement in a two-atom system with a common reservoir.

DOI: 10.1364/aop.2.000229

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