Simon Meynell: Silicon color centers: towards scalable distributed quantum computing

Abstract: To reach practical utility for a quantum computer, thousands to millions of qubits must be coherently linked, a task that has proven deeply challenging for monolithic systems. Distributed quantum computing sidesteps this challenge by entangling spatially disparate quantum processors, building large quantum systems without requiring any single node to scale. Quantum networks typically generate this entanglement via photonic interference, and thus an interface between the local processor and the photon is required. Color centers are natural candidates for this spin-photon interface, offering long-lived spin coherence and narrowband emission. Silicon color centers are particularly scalable because of their ready integration into existing fabrication pipelines and compatibility with on-chip photonic circuitry. While the pathway to building a nanophotonic-integrated network of silicon color centers is clear, the path to making that network fast and high-fidelity is not. In this talk, I will focus on one of the most promising silicon color centers, the T center, examining the physics governing two dominant limits on entanglement rate and fidelity: spectral diffusion, which disrupts photon indistinguishability, and optically-induced spin flips, which undermine the spin memory. We will see how leveraging that physical understanding enables us to mitigate both. I will show how these improvements inform our progress toward demonstration of spin-photon entanglement and time-bin encoded photonic qubits – a key primitive for long-distance quantum networks.

Bio: Simon Meynell is a postdoctoral research fellow at Simon Fraser University and Photonic Inc., where he develops silicon T center qubits for scalable quantum networking. He completed his PhD at UC Santa Barbara under Prof. Ania Bleszynski Jayich, studying many-body spin dynamics and quantum sensing using nitrogen-vacancy centers in diamond. His research centers on understanding how materials engineering and quantum control intersect to enable coherent solid-state spin systems, a thread he has followed from NV centers in diamond to optically active defects in silicon.