Daniel Higginbottom (Simon Fraser University), QISE Seminar: Engineering silicon colour centres for quantum networks

Abstract

The performance of quantum networks for long-distance communication, sensing, and distributed quantum computing will be contingent upon the quality of their light-matter interconnects. For networks at scale, these interconnects should be manufacturable and deployable. Solid-state colour centres are single-photon emitters which may offer optically-coupled spin qubit registers for deployable entanglement distribution networks. Of the potential semiconductor hosts, silicon is an ideal platform for commercial quantum technologies. It is a “semiconductor vacuum” with record-setting spin qubit performance, and silicon nanofabrication is an advanced industrial process and the backbone of the microelectronics industry. Although they were neglected until quite recently, silicon colour centres are now established as a quantum platform with technological appeal: they emit in or near the optical telecommunications bands, host intrinsic spin qubit registers, and integrate directly with photonic and electronic circuits on chip. In this talk I will discuss progress towards networked silicon colour centre devices and identify emerging candidates from the rapidly expanding alphabet of silicon colour centres. In particular, I will summarize recent results with the T centre, a CCH defect in silicon. A surprising isotope-dependent lifetime effect suggests that the T centre can be made almost perfectly efficient by isotopic substitution. Cavity-integrated T centres show dramatic Purcell enhancements, enabling faster and more coherent emission, and indistinguishable emission is employed to entangle T centres on separate chips, six meters apart. Determining the hyperfine tensors of the T centre’s intrinsic spin qubits reveals unusual schemes for protecting spin coherence during entanglement attempts. Finally, a new class of opto-electronic devices combining single emitters, optical resonators, and diodes enable a host of spin-photon control techniques including electrically-injected single-photon emission, Stark tuning, and electrical spin initialization. These results illustrate how silicon colour centres may be deployed as an on-chip spin-photon quantum processor, and how these processors may be connected over optical fibre in a metropolitan-scale quantum internet.

Bio

Dr Daniel Higginbottom is an Assistant Professor in the Simon Fraser University Department of Physics and a Director at the quantum technology company Photonic Inc. His research has spanned quantum information with platforms including integrated photonics, optically trapped atoms, electrically trapped ions, and silicon spin qubits, for which he received a Banting Research Fellowship. His achievements include benchmark results with single photon sources and optical quantum memories. Recently, he has pioneered the device integration of silicon colour centres, most notably the T centre, for quantum technologies. The primary goal of his research is developing practical, and scalable, quantum technology platforms.