An Entanglement Filter

TL;DR

This paper demonstrates an optical entanglement filter that selectively passes photon pairs with specific polarization correlations, advancing quantum information processing capabilities.

Contribution

It introduces a novel optical entanglement filter capable of filtering photon pairs based on their entanglement properties, extending single-qubit filtering techniques.

Findings

Successfully demonstrated the entanglement filter in an optical setup

The filter passes photon pairs with desired polarization correlations

Potential applications in quantum communication and computing

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.