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arXiv · 1309.0590

The role of singular values in entanglement distillation and unambiguous state discrimination

Raam Uzdin
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Abstract

Unambiguous (non-orthogonal) state discrimination (USD) has a fundamental importance in quantum information and quantum cryptography. Various aspects of two-state and multiple-state USD are studied here using singular value decomposition (SVD) of the evolution operator that describes a given state discriminating system. In particular, we relate the minimal angle between states to the ratio of the minimal and maximal singular values. This is supported by a simple geometrical picture in two-state USD. We apply our result to study what states can undergo entanglement distillation in a given system.

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Raam Uzdin. 2013-09-03. The role of singular values in entanglement distillation and unambiguous state discrimination. https://doi.org/10.1088/1751-8113%2F47%2F16%2F165301

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