title: An entanglement filter.
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.
authors.affiliation: Research Institute for Electronic Science, Hokkaido University, Sapporo 060-0812, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Okamoto
authors.forename: Jeremy L
authors.initials: JL
authors.lastname: O'Brien
authors.forename: Holger F
authors.initials: HF
authors.lastname: Hofmann
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Nagata
authors.forename: Keiji
authors.initials: K
authors.lastname: Sasaki
authors.forename: Shigeki
authors.initials: S
authors.lastname: Takeuchi