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Improving the Fidelity of Optical Zeno Gates via Distillation

P. M. Leung·T. C. Ralph
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Abstract

We have modelled the Zeno effect Control-Sign gate of Franson et al (PRA 70, 062302, 2004) and shown that high two-photon to one-photon absorption ratios, $\kappa$, are needed for high fidelity free standing operation. Hence we instead employ this gate for cluster state fusion, where the requirement for $\kappa$ is less restrictive. With the help of partially offline one-photon and two-photon distillations, we can achieve a fusion gate with unity fidelity but non-unit probability of success. We conclude that for $\kappa > 2200$, the Zeno fusion gate will out perform the equivalent linear optics gate.

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P. M. Leung, T. C. Ralph. 2006-09-29. Improving the Fidelity of Optical Zeno Gates via Distillation. https://doi.org/10.1103/physreva.74.062325

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