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arXiv:0707.3215

Many-Body Separability of Warm Qubits

Ting Yu, Joseph H. Eberly

Published Jul 23, 2007• 6 citations
arXivHTMLPDF

Abstract

We analyze the separability of the joint state of a collection of two-level systems at finite temperature T. The fact that only separable states are found in the neighborhood of their thermal equilibrium state guarantees that decoherence will destroy any initially arranged entanglement in a finite time.
DOI
10.48550/arxiv.0707.3215

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A complete treatment of the entanglement of two-level systems, which evolves through the contact with a thermal bath, must include the fact that the system and the bath are not fully separable. Therefore, quantum coherent superpositions of system and bath states, which are almost never fully included in theoretical models, are invariably present when an entangled state is prepared experimentally. We show their importance for the time evolution of the entanglement of two qubits coupled to independent baths. In addition, our treatment is able to handle slow and low-temperature thermal baths.
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