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arXiv:0905.3057 · Open Systems & Information Dynamics

A Simple Thermodynamical Witness Showing Universality of Macroscopic Entanglement

Vlatko Vedral

Published Aug 13, 2009• 4 citations
arXivHTMLPDF

Abstract

We show that if the ground state entanglement exceeds the total entropy of a given system, then this system is in an entangled state. This is a universal entanglement witness that applies to any physical system and yields a temperature below which we are certain to find some entanglement. Our witness is then applied to generic bosonic and fermionic many-body systems to derive the corresponding "critical" temperatures that have a very broad validity.

DOI
10.1142/s1230161209000220

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