Qubit entanglement between ring-resonator photon-pair sources on a silicon chip

Silverstone, J.W., Santagati, R., Bonneau, D., Strain, M.J., Sorel, M. , O’Brien, J. L. and Thompson, M. G. (2015) Qubit entanglement between ring-resonator photon-pair sources on a silicon chip. Nature Communications, 6, 7948. (doi: 10.1038/ncomms8948) (PMID:26245267) (PMCID:PMC4918336)

Abstract

Entanglement—one of the most delicate phenomena in nature—is an essential resource for quantum information applications. Scalable photonic quantum devices must generate and control qubit entanglement on-chip, where quantum information is naturally encoded in photon path. Here we report a silicon photonic chip that uses resonant-enhanced photon-pair sources, spectral demultiplexers and reconfigurable optics to generate a path-entangled two-qubit state and analyse its entanglement. We show that ring-resonator-based spontaneous four-wave mixing photon-pair sources can be made highly indistinguishable and that their spectral correlations are small. We use on-chip frequency demultiplexers and reconfigurable optics to perform both quantum state tomography and the strict Bell-CHSH test, both of which confirm a high level of on-chip entanglement. This work demonstrates the integration of high-performance components that will be essential for building quantum devices and systems to harness photonic entanglement on the large scale.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Sorel, Professor Marc and Strain, Dr Michael
• Authors: Silverstone, J.W., Santagati, R., Bonneau, D., Strain, M.J., Sorel, M., O’Brien, J. L., and Thompson, M. G.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: Nature Communications
• Publisher: Nature Publishing Group
• ISSN: 2041-1723
• ISSN (Online): 2041-1723
• Copyright Holders: Copyright © 2015 Macmillan Publishers Limited
• First Published: First published in Nature Communications 6:7948
• Publisher Policy: Reproduced under a Creative Commons License