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arXiv · 0804.0992

Methods for linear optical quantum Fredkin gate

Yan-Xiao Gong·Guang-Can Guo·Timothy C. Ralph
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Abstract

We consider the realization of quantum Fredkin gate with only linear optics and single photons. First we construct a heralded Fredkin gate using four heralded controlled-not (CNOT) gates. Then we simplify this method to a post-selected one utilizing only two CNOT gates. We also give a possible realization of this method which is feasible with current experimental technology. Another post-selected scheme requires time entanglement of the input photons but needs no ancillary photons.

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Yan-Xiao Gong, Guang-Can Guo, Timothy C. Ralph. 2008-04-07. Methods for linear optical quantum Fredkin gate. https://doi.org/10.1103/physreva.78.012305

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