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Minimum output entropy of bosonic channels: a conjecture

Vittorio Giovannetti·Saikat Guha·Seth Lloyd·Lorenzo Maccone·Jeffrey H. Shapiro
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Abstract

The von Neumann entropy at the output of a bosonic channel with thermal noise is analyzed. Coherent-state inputs are conjectured to minimize this output entropy. Physical and mathematical evidence in support of the conjecture is provided. A stronger conjecture--that output states resulting from coherent-state inputs majorize the output states from other inputs--is also discussed.

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Vittorio Giovannetti, Saikat Guha, Seth Lloyd, Lorenzo Maccone, Jeffrey H. Shapiro. 2004-04-01. Minimum output entropy of bosonic channels: a conjecture. https://doi.org/10.1103/physreva.70.032315

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