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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Investigation of two qubit quantum gates in linear optics

Timothy C. Ralph, Nathan K. Langford, T. B. Bell, Jeremy L. O’Brien, Geoff J. Pryde, Andrew G. White, Gerard J Milburn

Published Feb 3, 2004• 6 citations
Publisher

Abstract

We discuss progress towards implementing two qubit quantum gates in optics. We review the operation of an optical quantum gate which performs all the operations of a control-NOT (CNOT) gate in the coincidence basis with two, unentangled photons as the input and discuss its implementation.
DOI
10.1117/12.505078

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We describe the operation and tolerances of a nondeterministic, coincidence basis, quantum controlled-NOT gate for photonic qubits. It is constructed solely from linear optical elements and requires only a two-photon source for its demonstration. Its success probability is 1/9.1/9.1/9.
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