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arXiv · 0711.4212

Quantum cloning a pair of orthogonally polarized photons with linear optics

Jaromir Fiurasek·Nicolas J. Cerf
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Abstract

A linear optical probabilistic scheme for the optimal cloning of a pair of orthogonally-polarized photons is devised, based on single- and two-photon interferences. It consists in a partial symmetrization device, realized with a modified unbalanced Mach-Zehnder interferometer, followed by two independent Hong-Ou-Mandel interferometers. This scheme has the advantage that it enables quantum cloning without the need for stimulated amplification in a nonlinear medium. It can also be modified so to make an optical two-qubit partial SWAP gate, thereby providing a potentially useful tool to linear optics quantum computing.

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Jaromir Fiurasek, Nicolas J. Cerf. 2007-11-27. Quantum cloning a pair of orthogonally polarized photons with linear optics. https://doi.org/10.1103/physreva.77.052308

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