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Unambiguous Discrimination Between Linearly-Independent Quantum States

Anthony Chefles
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Abstract

The theory of generalised measurements is used to examine the problem of discriminating unambiguously between non-orthogonal pure quantum states. Measurements of this type never give erroneous results, although, in general, there will be a non-zero probability of a result being inconclusive. It is shown that only linearly-independent states can be unambiguously discriminated. In addition to examining the general properties of such measurements, we discuss their application to entanglement concentration.

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Anthony Chefles. 1998-07-08. Unambiguous Discrimination Between Linearly-Independent Quantum States. https://doi.org/10.1016/s0375-9601(98)00064-4

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