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Experimental Demonstration of Optimal Unambiguous State Discrimination

Roger B. M. Clarke·Anthony Chefles·Stephen M. Barnett·Erling Riis
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Abstract

We present the first full demonstration of unambiguous state discrimination between non-orthogonal quantum states. Using a novel free space interferometer we have realised the optimum quantum measurement scheme for two non-orthogonal states of light, known as the Ivanovic-Dieks-Peres (IDP) measurement. We have for the first time gained access to all three possible outcomes of this measurement. All aspects of this generalised measurement scheme, including its superiority over a standard von Neumann measurement, have been demonstrated within 1.5% of the IDP predictions.

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Roger B. M. Clarke, Anthony Chefles, Stephen M. Barnett, Erling Riis. 2000-07-19. Experimental Demonstration of Optimal Unambiguous State Discrimination. https://doi.org/10.1103/physreva.63.040305

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