Quantum Emitters for Telecommunication in the O-Band

Quantum communication is a transformative technology that can address our society’s need for secure communication and form the backbone for networks of quantum computers. 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. This platform will 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.

QuanTELCO will exploit a mature material platform (silicon carbide), fully compatible with standard industrial micro-electronic fabrication processes. The quantum emitters employed in QuanTELCO have optical cross sections that are orders of magnitude greater than many currently leading candidates. 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 leverage these properties to demonstrate all key elements of quantum networking.

An overview of quantum Repeater technology is available in recent reviews

Wei, S.-H., Jing, B., Zhang, X.-Y., Liao, J.-Y., Yuan, C.-Z., Fan, B.-Y., Lyu, C., Zhou, D.-L., Wang, Y., Deng, G.-W., Song, H.-Z., Oblak, D., Guo, G.-C., Zhou, Q., Towards Real-World Quantum Networks: A Review. Laser & Photonics Reviews 2022, 16, 2100219. https://doi.org/10.1002/lpor.202100219

van Loock, P., Alt, W., Becher, C., Benson, O., Boche, H., Deppe, C., Eschner, J., Höfling, S., Meschede, D., Michler, P., Schmidt, F. and Weinfurter, H. (2020), Extending Quantum Links: Modules for Fiber- and Memory-Based Quantum Repeaters. Adv. Quantum Technol., 3: 1900141. https://doi.org/10.1002/qute.201900141