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arXiv:0709.1651 · Physical Review A

Local distinguishability of orthogonal 2⊗3 pure states

Yu Xin, Runyao Duan

Published Jan 14, 2008• 37 citations
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Abstract

We present a complete characterization for the local distinguishability of orthogonal $2\ensuremath{\bigotimes}3$ pure states except for some special cases of three states. Interestingly, we find there is a large class of four or three states that are indistinguishable by local projective measurements and classical communication (LPCC), but can be perfectly distinguished by LOCC. That indicates the ability of LOCC for discriminating $2\ensuremath{\bigotimes}3$ states is strictly more powerful than that of LPCC, which is strikingly different from the case of multiqubit states. We also show that classical communication plays a crucial role for local distinguishability by constructing a class of $m\ensuremath{\bigotimes}n$ states which require at least $2\phantom{\rule{0.2em}{0ex}}\mathrm{min}{m,n}\ensuremath{-}2$ rounds of classical communication in order to achieve a perfect local discrimination.

DOI
10.1103/physreva.77.012315

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