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arXiv:quant-ph/0206018 · Journal of Optics B Quantum and Semiclassical Optics

Enhancement of thermal entanglement in two-qubit XY models

Celia Anteneodo, Andr  M C Souza

Published Jan 20, 2003• 26 citations
arXivHTMLPDF

Abstract

We analyse conditions leading to enhancement of thermal entanglement in two-qubit XY models. The effect of including cross-product terms, besides the standard XY exchange interactions, in the presence of an external magnetic field, is investigated. We show that entanglement can be yielded at elevated temperatures by tuning the orientation of the external magnetic field. The details of the intrinsic exchange interactions determine the optimal orientation.

DOI
10.1088/1464-4266/5/1/310

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