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Efficiency limits for linear optical processing of single photons and single-rail qubits

Dominic W. Berry·A. I. Lvovsky·Barry C. Sanders
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Abstract

We analyze the problem of increasing the efficiency of single-photon sources or single-rail photonic qubits via linear optical processing and destructive conditional measurements. In contrast to previous work we allow for the use of coherent states and do not limit to photon-counting measurements. We conjecture that it is not possible to increase the efficiency, prove this conjecture for several important special cases, and provide extensive numerical results for the general case.

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Dominic W. Berry, A. I. Lvovsky, Barry C. Sanders. 2006-05-03. Efficiency limits for linear optical processing of single photons and single-rail qubits. https://doi.org/10.1364/josab.24.000189

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