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Coherent Communication with Continuous Quantum Variables

Mark M. Wilde·Hari Krovi·Todd A. Brun
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Abstract

The coherent bit (cobit) channel is a resource intermediate between classical and quantum communication. It produces coherent versions of teleportation and superdense coding. We extend the cobit channel to continuous variables by providing a definition of the coherent nat (conat) channel. We construct several coherent protocols that use both a position-quadrature and a momentum-quadrature conat channel with finite squeezing. Finally, we show that the quality of squeezing diminishes through successive compositions of coherent teleportation and superdense coding.

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Mark M. Wilde, Hari Krovi, Todd A. Brun. 2006-12-20. Coherent Communication with Continuous Quantum Variables. https://doi.org/10.1103/physreva.75.060303

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