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Capacities of Quantum Channels for Massive Bosons and Fermions

Aditi Sen De·Ujjwal Sen·Bartosz Gromek·Dagmar Bruss·Maciej Lewenstein
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Abstract

We consider the capacity of classical information transfer for noiseless quantum channels carrying a finite average number of massive bosons and fermions. The maximum capacity is attained by transferring the Fock states generated from the grand-canonical ensemble. Interestingly, the channel capacity for a Bose gas indicates the onset of a Bose-Einstein condensation, by changing its qualitative behavior at the criticality, while for a channel carrying weakly attractive fermions, it exhibits the signatures of Bardeen-Cooper-Schrieffer transition. We also show that for noninteracting particles, fermions are better carriers of information than bosons.

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Aditi Sen De, Ujjwal Sen, Bartosz Gromek, Dagmar Bruss, Maciej Lewenstein. 2006-01-08. Capacities of Quantum Channels for Massive Bosons and Fermions. https://doi.org/10.1103/physrevlett.95.260503

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