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Remote preparation of a single-mode photonic qubit by measuring field quadrature noise

S. A. Babichev·B. Brezger·A. I. Lvovsky
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Abstract

An electromagnetic field quadrature measurement, performed on one of the modes of the nonlocal single-photon state $a|1,0>-b|0,1>$, collapses it into a superposition of the single-photon and vacuum states in the other mode. We use this effect to implement remote preparation of arbitrary single-mode photonic qubits conditioned on observation of a preselected quadrature value. The quantum efficiency of the prepared qubit can be higher than that of the initial single photon.

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S. A. Babichev, B. Brezger, A. I. Lvovsky. 2003-08-25. Remote preparation of a single-mode photonic qubit by measuring field quadrature noise. https://doi.org/10.1103/physrevlett.92.047903

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