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arXiv · 1002.2819

Sub-shot-noise-limit discrimination of on-off keyed coherent signals via a quantum receiver with a superconducting transition edge sensor

Kenji Tsujino·Daiji Fukuda·Go Fujii·Shuichiro Inoue·Mikio Fujiwara·Masahiro Takeoka·Masahide Sasaki
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Abstract

We demonstrate a sub-shot-noise-limit discrimination of on-off keyed coherent signals by an optimal displacement quantum receiver in which a superconducting transition edge sensor is installed. Use of a transition edge sensor and a fiber beam splitter realizes high total detection efficiency and high interference visibility of the receiver and the observed average error surpasses the shot-noise-limit in a wider range of the signal power. Our technique opens up a new technology for the sub-shot-noise-limit detection of coherent signals in optical communication channels.

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Kenji Tsujino, Daiji Fukuda, Go Fujii, Shuichiro Inoue, Mikio Fujiwara, Masahiro Takeoka, Masahide Sasaki. 2010-02-15. Sub-shot-noise-limit discrimination of on-off keyed coherent signals via a quantum receiver with a superconducting transition edge sensor. https://doi.org/10.1364/oe.18.008107

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