Scalable Fault-Tolerant Quantum Technologies with Silicon Colour Centres

Abstract: The scaling barriers currently faced by both quantum networking and quantum computing technologies ultimately amount to the same core challenge of distributing high-quality entanglement at scale. In this Perspective, a novel quantum information processing architecture based on optically active spins in silicon is proposed that offers a combined single technological platform for scalable fault-tolerant quantum computing and networking. The architecture is optimized for overall entanglement distribution and leverages colour centre spins in silicon (T centres) for their manufacturability, photonic interface, and high fidelity information processing properties. Silicon nanophotonic optical circuits allow for photonic links between T centres, which are networked via telecom-band optical photons in a highly-connected graph. This high connectivity unlocks the use of low-overhead quantum error correction codes, significantly accelerating the timeline for modular, scalable fault-tolerant quantum repeaters and quantum processors.