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arXiv:0905.0074 · Science

An Entanglement Filter

Ryo Okamoto, Jeremy L. O’Brien, Holger Friedrich Hofmann, Tomohisa Nagata, Keiji Sasaki, Shigeki Takeuchi

Published Jan 22, 2009• 87 citations
arXivHTMLPDF

Abstract

The ability to filter quantum states is a key capability in quantum information science and technology, in which one-qubit filters, or polarizers, have found wide application. Filtering on the basis of entanglement requires extension to multi-qubit filters with qubit-qubit interactions. We demonstrated an optical entanglement filter that passes a pair of photons if they have the desired correlations of their polarization. Such devices have many important applications to quantum technologies.

DOI
10.1126/science.1167182

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