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arXiv · 0705.3391

Commutator Relations Reveal Solvable Structures in Unambiguous State Discrimination

M. Kleinmann·H. Kampermann·Ph. Raynal·D. Bruss
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Abstract

We present a criterion, based on three commutator relations, that allows to decide whether two self-adjoint matrices with non-overlapping support are simultaneously unitarily similar to quasidiagonal matrices, i.e., whether they can be simultaneously brought into a diagonal structure with 2x2-dimensional blocks. Application of this criterion to unambiguous state discrimination provides a systematic test whether the given problem is reducible to a solvable structure. As an example, we discuss unambiguous state comparison.

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M. Kleinmann, H. Kampermann, Ph. Raynal, D. Bruss. 2007-05-31. Commutator Relations Reveal Solvable Structures in Unambiguous State Discrimination. https://doi.org/10.1088/1751-8113/40/36/f04

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