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arXiv · 0810.1970

Quantum state discrimination

Stephen M. Barnett·Sarah Croke
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Abstract

It is a fundamental consequence of the superposition principle for quantum states that there must exist non-orthogonal states, that is states that, although different, have a non-zero overlap. This finite overlap means that there is no way of determining with certainty in which of two such states a given physical system has been prepared. We review the various strategies that have been devised to discriminate optimally between non-orthogonal states and some of the optical experiments that have been performed to realise these.

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Stephen M. Barnett, Sarah Croke. 2008-10-10. Quantum state discrimination. https://arxiv.org/abs/0810.1970

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