In Step Toward Quantum Networking, Penn Study Finds Quantum Light Pattern Can Survive Loss of Entanglement
University of Pennsylvania researchers, with collaborators at the University of the Witwatersrand and Nanyang Technological University, used a silicon nitride photonic chip to transfer a topological winding pattern into two-photon correlations. They measured the skyrmion number while a standard entanglement measure fell to zero and found the topological number remained stable. The researchers attribute this persistence to quantum discord, suggesting a possible route to noise-resilient quantum network links.
Within the next two years, this could enable photonic quantum network testbeds to use quantum discord or skyrmion number as a supplementary link quality signal, allowing short-reach links to operate in noise regimes where conventional entanglement certifiers fail.