A quantum internet will revolutionize communication technology by exploiting phenomena from quantum physics. Despite recent successes in the deployment of secure quantum cryptographic keys, the lack of telecom-wavelength repeaters operating at the quantum level presents a major bottleneck to realizing a global-scale quantum communication network. The EU-funded QuanTELCO project will overcome this challenge by exploiting specific spin centres in silicon carbide which possess strong optical transitions in the telecom O-band. These quantum emitters furthermore host electronic and nuclear spins that can act as memories in quantum repeater nodes. Such a breakthrough should help create robust, transcontinental quantum information links compatible with existing infrastructure, ushering in the era of quantum-encrypted communications and networked quantum computing in Europe.
Despite recent successes in the deployment of secure quantum cryptographic keys, the unavailability of telecom-wavelength repeaters operating at the quantum level presents a major bottleneck towards a global-scale quantum communication network. QuanTELCO will overcome this bottleneck by employing a radically transformative approach based on telecom-wavelength spin centres in silicon carbide, recently discovered by our consortium. These centres uniquely possess strong optical transitions in the telecom O-band (1260-1360 nm), in a material widely used by the micro-electronics industry. QuanTELCO will exploit a mature material platform (silicon carbide), fully compatible with standard industrial micro-electronic fabrication processes. Their emission wavelength allows direct, low-loss propagation in existing telecom networks without the detrimental losses caused by wavelength conversion. These emitters host electronic and nuclear spins which can act as memories in quantum repeater nodes. QuanTELCO will perform an in-depth study of these properties in order to demonstrate all key elements of quantum networking. QuanTELCO will distil the project results to deliver a roadmap for commercial deployment based on real-world, actionable insight. In summary, the project aim is to provide the breakthrough required for the creation of robust, transcontinental quantum information links, compatible with existing infrastructure, thereby ushering in the era of physically secure encryption and networked quantum computation across Europe.