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Minimum Renyi and Wehrl entropies at the output of bosonic channels

Vittorio Giovannetti·Seth Lloyd·Lorenzo Maccone·Jeffrey H. Shapiro·Brent J. Yen
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Abstract

The minimum Renyi and Wehrl output entropies are found for bosonic channels in which the signal photons are either randomly displaced by a Gaussian distribution (classical-noise channel), or in which they are coupled to a thermal environment through lossy propagation (thermal-noise channel). It is shown that the Renyi output entropies of integer orders z>1 and the output Wehrl entropy are minimized when the channel input is a coherent state.

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Vittorio Giovannetti, Seth Lloyd, Lorenzo Maccone, Jeffrey H. Shapiro, Brent J. Yen. 2004-05-19. Minimum Renyi and Wehrl entropies at the output of bosonic channels. https://doi.org/10.1103/physreva.70.022328

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