Optical observation of single spins in silicon

TL;DR

This paper demonstrates the creation and optical characterization of single photon-spin qubits in silicon, advancing the development of scalable quantum networks compatible with existing telecommunications infrastructure.

Contribution

It reports the first production and detailed optical analysis of individually addressable photon-spin qubits in silicon, a key step toward scalable quantum communication.

Findings

Produced tens of thousands of $T$ centre photon-spin qubits in silicon.

Characterized their spin-dependent optical transitions in the telecommunications band.

Showed potential for integrated silicon quantum networks.

Abstract

The global quantum internet will require long-lived, telecommunications band photon-matter interfaces manufactured at scale. Preliminary quantum networks based upon photon-matter interfaces which meet a subset of these demands are encouraging efforts to identify new high-performance alternatives. Silicon is an ideal host for commercial-scale solid-state quantum technologies. It is already an advanced platform within the global integrated photonics and microelectronics industries, as well as host to record-setting long-lived spin qubits. Despite the overwhelming potential of the silicon quantum platform, the optical detection of individually addressable photon-spin interfaces in silicon has remained elusive. In this work we produce tens of thousands of individually addressable `$T$ centre' photon-spin qubits in integrated silicon photonic structures, and characterize their spin-dependent telecommunications-band optical transitions. These results unlock immediate opportunities to construct silicon-integrated, telecommunications-band quantum information networks.