<?xml version="1.0" encoding="UTF-8"?><ns2:project xmlns:ns1="http://gtr.rcuk.ac.uk/gtr/api" xmlns:ns2="http://gtr.rcuk.ac.uk/gtr/api/project" xmlns:ns3="http://gtr.rcuk.ac.uk/gtr/api/fund" xmlns:ns4="http://gtr.rcuk.ac.uk/gtr/api/person" xmlns:ns5="http://gtr.rcuk.ac.uk/gtr/api/project/outcome" xmlns:ns6="http://gtr.rcuk.ac.uk/gtr/api/organisation" ns1:created="2026-06-22T07:57:45Z" ns1:href="http://gtr.ukri.org/gtr/api/projects/64483197-1ED8-407E-A8E8-7106ADC48385" ns1:id="64483197-1ED8-407E-A8E8-7106ADC48385"><ns1:links><ns1:link ns1:href="http://gtr.ukri.org/gtr/api/persons/51AC0B8F-05E2-4EA6-8A59-622052D0A7BE" ns1:rel="PM_PER"/><ns1:link ns1:href="http://gtr.ukri.org/gtr/api/organisations/792035D9-F030-45DE-81E9-C6A79A0F0C9F" ns1:rel="LEAD_ORG"/><ns1:link ns1:href="http://gtr.ukri.org/gtr/api/organisations/792035D9-F030-45DE-81E9-C6A79A0F0C9F" ns1:rel="PARTICIPANT_ORG"/><ns1:link ns1:end="2025-07-30T23:00:00Z" ns1:href="http://gtr.ukri.org/gtr/api/funds/0AA1DEAB-B729-419A-9AF9-35355790AA78" ns1:rel="FUND" ns1:start="2025-03-31T23:00:00Z"/></ns1:links><ns2:identifiers><ns2:identifier ns2:type="RCUK">10157643</ns2:identifier></ns2:identifiers><ns2:title>RingCryption: Scalable and Cooler-free Single-Photon Sources for Quantum-Secure Communication at Telecoms Wavelengths</ns2:title><ns2:status>Closed</ns2:status><ns2:grantCategory>Collaborative R&amp;D</ns2:grantCategory><ns2:leadFunder>Innovate UK</ns2:leadFunder><ns2:abstractText>The rapid advancement of quantum computing poses a significant threat to existing cybersecurity systems by undermining traditional encryption methods like RSA and ECC. This escalating risk has created an urgent demand for quantum-secure communication technologies that can protect sensitive data across industries. Quantum-ring single-photon light-emitting diodes (QR-SPLEDs) address this cybersecurity challenge by offering a scalable and cost-effective solution for quantum key distribution (QKD), providing a practical, market-ready pathway to unbreakable encryption. QR-SPLEDs emit single photons on demand at telecoms wavelengths, ensuring seamless integration with existing fibre-optic telecommunications network infrastructure.

Unlike alternative sources that require cryogenic cooling or complex optical setups, QR-SPLEDs operate efficiently at room temperature through an all-electrical process. These unique semiconductor devices integrate GaSb quantum rings (QRs) in an optical cavity for photon emission at a specific wavelength. A quantum dot (QD) tunnelling layer enables precise electrical control over single-photon emission by injection of a single electron into the QRs. This concept is radically different to the conventional approach of trying to isolate a single light-emitting nanostructure, which is not scalable. Our QD single-electron filter layer dramatically simplifies the manufacturing process, facilitating scalable, high-yield production using standard semiconductor fabrication techniques that are already used to produce billions of vertical-cavity surface-emitting lasers (VCSELs) at very low cost. QR SPLEDs compact form factor and low power consumption make them ideal for real-world cybersecurity applications, particularly for industries such as telecommunications, finance, defence and healthcare, where secure data transmission is critical.

Our technology has demonstrated strong proof-of-principle results with spectrally-pure (cavity-enhanced) photon emission at temperatures up to 80&amp;deg;C. Participation in the Innovate UK ICURe Explore Future Telecoms and NW CyberCom programmes has identified both the technological feasibility and market demand for QR-SPLEDs. The CyberASAP programme will further refine our cybersecurity commercialisation strategy, ensuring QR-SPLEDs meet the pressing needs of industries grappling with quantum-era cyber threats.

Industry feedback highlights a pressing need for room-temperature, telecom-compatible and cost-effective single-photon sources, positioning QR-SPLEDs as a game-changing cybersecurity technology against the looming threat of quantum-enabled cyberattacks. The project will build on this, delivering robust value propositions and strong market validation in preparation for spinning-out within the next year.

The global quantum communication market is projected to exceed $15 billion by 2030, driven by the need for quantum-secure encryption solutions. QR-SPLEDs fill a critical market gap by delivering compact, efficient, and affordable single-photon sources, uniquely suited for large-scale deployment in cybersecurity systems worldwide.</ns2:abstractText></ns2:project>