Waveguide-integrated silicon T centres

A key step towards quantum technologies is the deployment of a qubit within a modular platform, one that can achieve the large scales necessary for practical computation and communication. One path to this modular design is the use of optically linked quantum networks for distributed computing. The T centre provides many advantages for realizing such a technology. Possessing a photonic degree of freedom in the telecommunications band along with long-lived electron and nuclear spins all while being native to silicon – the proven leader for modular, scalable architectures in both electronics and photonics. Recent work has shown that T centres can be reliably integrated into commercially available silicon-on-insulator wafer and here we take the next step in integrating T centres into waveguide devices suitable for building up modular networks. We demonstrate optical control of the T centre spin ensembles and measure long spin lifetimes. Next we perform hole burning to reveal homogeneous linewidths more than an order of magnitude narrower than previous estimates and forecast that remote entanglement operations are within reach with only modest cavity Purcell enhancements. Finally, we investigate the performance ceiling of the T centre ensembles via hole burning on bulk isotopically purified silicon showcasing a homogeneous linewidth nearly at the lifetime limit. These measurements further solidify the T centre as a promising qubit candidate for deployment into modular platforms in the near future.