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International Journal of Quantum Information

THERMAL ENHANCEMENT OF ENTANGLEMENT SENSITIVITY TO THE PHASE DIAGRAM IN XY MODEL

Yoshifumi Nakata, Damian Markham, Mio Murao

Published Jul 1, 2008• 0 citations
Publisher

Abstract

To understand multi-partite entanglement of the thermal state in the 1D spin 1/2 XY model with a transverse magnetic field, we investigate the temperature below which the thermal state is certainly entangled. We refer to such a temperature as a threshold temperature. We show that two characteristic lines in the phase diagram at zero temperature of the XY model can be clearly emphasized by the threshold temperature.

DOI
10.1142/s0219749908004067

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