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Concatenated beam splitters, optical feed-forward and the nonlinear sign gate

Kurt Jacobs·Jonathan P. Dowling
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Abstract

We consider a nonlinear sign gate implemented using a sequence of two beam splitters, and consider the use of further sequences of beam splitters to implement feed-forward so as to correct an error resulting from the first beam splitter. We obtain similar results to Scheel et al. [Scheel et al., Phys. Rev. A 73, 034301 (2006)], in that we also find that our feed-forward procedure is only able to produce a very minor improvement in the success probability of the original gate.

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Kurt Jacobs, Jonathan P. Dowling. 2006-06-26. Concatenated beam splitters, optical feed-forward and the nonlinear sign gate. https://doi.org/10.1103/physreva.74.064304

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