Physical Review A

Comparison of error probability bounds in quantum state discrimination

Roberto Corvaja

Published Apr 23, 2013• 3 citations

Abstract

In quantum discrimination, the value of the minimum error probability and the set of measurement operators which achieve this minimum are often difficult to derive. Here we present a comparison of the performance obtained by the optimal solution and by the available bounds, namely the square root measurement (SRM) and the Chernoff bound. Applied to some Gaussian states, namely to coherent states with thermal noise, it is shown that the SRM provides a much tighter bound with respect to the Chernoff bound, with a comparable numerical complexity.

DOI: 10.1103/physreva.87.042329

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