Electrically tunable, two-photon interference from remote silicon-vacancy centers in industrial silicon carbide
Year: 2026
Type: preprint
Abstract: Distributed quantum networks rely on spatially separated, independently operated quantum systems as network nodes, whose emitted photons must be interfered with high visibility to establish end-to-end entanglement. Crucially, for network-relevant applications, high visibilities must be achieved over prolonged timescales to reduce overheads for error correction, and to increase network rates. Here, we demonstrate experimentally that silicon vacancy $\mathrm{V_{Si}}$ color centers in silicon carbide (SiC) achieve these requirements, notably in a mass-deployable fashion. We integrate $\mathrm{V_{Si}}$ centers in different industrial-grade SiC p-i-n diodes, which are controlled via voltage biassing. This way, we demonstrate both, spectral overlapping of 19 randomly selected $\mathrm{V_{Si}}$ centers in different diodes, as well as spectral narrowing close to the lifetime limit, i.e., typically below 60 MHz. Notably, these performance parameters are long-term stable, e.g., readjusting the p-i-n diode bias is required only every 8.4 hours, which reduces significantly the overall experimental overhead. We then use these assets to demonstrate high-quality two-photon interference between $\mathrm{V_{Si}}$ centers located in two different cryostat setups, which are spatially separated by two meters. Notably, we perform a 26-days long measurement campaign, demonstrating two-photon interference with state-of-the-art raw interference visibilities of 82%, which aligns with the current state-of-the-art. These results establish $\mathrm{V_{Si}}$ centers in industry-grade SiC devices as a scalable, spectrally stable building block for distributed quantum networks.
Source: arXiv (Cornell University)
Institutions: Friedrich-Alexander-Universität Erlangen-Nürnberg, Fraunhofer Institute for Integrated Systems and Device Technology, University of Stuttgart, Center for Integrated Quantum Science and Technology, Leibniz Institute of Surface Engineering, University of Luxembourg, Luxembourg Institute of Science and Technology
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: green
Awards: G1171162939, INNOBATT - Eine Batterie vom Material bis zum System neu denken - ressourcenschonend, leistungsstark, innovativ, Quantum Internet Alliance - Phase1, G2328963329, G415594430, QuaLiProM - Inline Qualitätskontrolle von Lithium-Ionen-Zellen in der Zellproduktion und Restwertanalyse gealterter Zellen im Recyclingprozess: SoH-Bestimmung mithilfe von Quantenmagnetometrie, G5595288094, Joined-up land use strategies tackling climate change and biodiversity loss, QuantERA II ERA-NET Cofund in Quantum Technologies, G6624113701, G7469808577, Quantum System-on-Chip based on silicon carbide, Trusted lifetime in operation for a circular economy, G8784154652
OpenAlex ID: W7212149850