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arXiv · 1101.1550

Structured optical receivers to attain superadditive capacity and the Holevo limit

Saikat Guha
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Abstract

When classical information is sent over a quantum channel, attaining the ultimate limit to channel capacity requires the receiver to make joint measurements over long codeword blocks. For a pure-state channel, we construct a receiver that can attain the ultimate capacity by applying a single-shot unitary transformation on the received quantum codeword followed by simultaneous (but separable) projective measurements on the single-modulation-symbol state spaces. We study the ultimate limits of photon-information-efficient communications on a lossy bosonic channel. Based on our general results for the pure-state quantum channel, we show some of the first concrete examples of codes and structured joint-detection optical receivers that can achieve fundamentally higher (superadditive) channel capacity than conventional receivers that detect each modulation symbol individually.

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Saikat Guha. 2011-01-07. Structured optical receivers to attain superadditive capacity and the Holevo limit. https://doi.org/10.1103/physrevlett.106.240502

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