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Alternate Scheme for Optical Cluster-State Generation without Number-Resolving Photon Detectors

Mark M. Wilde·Federico Spedalieri·Jonathan P. Dowling·Hwang Lee
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Abstract

We design a controlled-phase gate for linear optical quantum computing by using photodetectors that cannot resolve photon number. An intrinsic error-correction circuit corrects errors introduced by the detectors. Our controlled-phase gate has a 1/4 success probability. Recent development in cluster-state quantum computing has shown that a two-qubit gate with non-zero success probability can build an arbitrarily large cluster state with only polynomial overhead. Hence, it is possible to generate optical cluster states without number-resolving detectors and with polynomial overhead.

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Mark M. Wilde, Federico Spedalieri, Jonathan P. Dowling, Hwang Lee. 2007-05-22. Alternate Scheme for Optical Cluster-State Generation without Number-Resolving Photon Detectors. https://doi.org/10.1142/s0219749907003080

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