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Demonstration of a simple entangling optical gate and its use in Bell-state analysis

N. K. Langford·T. J. Weinhold·R. Prevedel·K. J. Resch·A. Gilchrist·J. L. O'Brien·G. J. Pryde·A. G. White
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Abstract

We demonstrate a new architecture for an optical entangling gate that is significantly simpler than previous realisations, using partially-polarising beamsplitters so that only a single optical mode-matching condition is required. We demonstrate operation of a controlled-Z gate in both continuous-wave and pulsed regimes of operation, fully characterising it in each case using quantum process tomography. We also demonstrate a fully-resolving, nondeterministic optical Bell-state analyser based on this controlled-Z gate. This new architecture is ideally suited to guided optics implementations of optical gates.

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N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O'Brien, G. J. Pryde, A. G. White. 2005-06-30. Demonstration of a simple entangling optical gate and its use in Bell-state analysis. https://doi.org/10.1103/physrevlett.95.210504

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