Efficiency limits for linear optical processing of single photons and single-rail qubits
نویسندگان
چکیده
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. We allow for the use of coherent states and do not limit to photon-counting measurements. We conjecture that, with the limitation that multiphoton components in the output are not permitted, it is not possible to increase the efficiency. We prove this conjecture for several important special cases, and provide extensive numerical results for the general case. © 2007 Optical Society of America OCIS codes: 270.5290.
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تاریخ انتشار 2006