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arXiv:0804.0992 · Physical Review A

Methods for a linear optical quantum Fredkin gate

Yan-Xiao Gong, Guang‐Can Guo, Timothy C. Ralph

Published Jul 2, 2008• 57 citations
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Abstract

We consider the realization of a 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.

DOI
10.1103/physreva.78.012305

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