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arXiv · 0707.4401

Entanglement measures: state ordering vs local operations

Mario Ziman·Vladimir Buzek
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Abstract

A set of all states of a bi-partite quantum system can be divided into subsets each of which contains states with the same degree of entanglement. In this paper we address a question whether local operations (without classical communication) affect the entanglement-induced state ordering. We show that arbitrary unilocal channel (i.e., a channel that acts on one sub-system of a bi-partite system only) might change the ordering for an arbitrary nontrivial measure of entanglement. A slightly weaker result holds for the maximally entangled states. In particular, the maximally entangled states might not remain the most entangled ones at the output of a unilocal noise channel.

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Mario Ziman, Vladimir Buzek. 2007-07-30. Entanglement measures: state ordering vs local operations. https://arxiv.org/abs/0707.4401

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