Spins Interfaced with Light for Quantum Silicon technologies

Leveraging the success of the microelectronics and integrated photonics industries, silicon is one of the most promising platforms for developing large-scale quantum technologies.

Quantum chips already available in silicon rely on either long-lived electrical qubits based on individual quantum dots or single donors, or on photonic qubits probabilistically generated by non-linear optical processes.

Another type of quantum system could combine the advantages of both former qubits by featuring at the same time a stationary qubit with long coherence times and an optical interface adapted to long-distance exchange of quantum information. However, such a qubit that would be associated to optically-active spin defects is still to be demonstrated in silicon.

This is the challenging objective of the current project.

The starting point of the SILEQS project is the recent discovery that silicon hosts many fluorescent point defects that can be optically isolated at single scale, and furthermore emit at the near-infrared range and telecom bands associated with minimal losses in optical fibers.

This project aims to demonstrate for the first time in silicon (1) the indistinguishable single-photon emission from individual defects and (2) the control over their spin degrees of freedom to create multi-spin quantum registers coupled to single photons.

Such achievements would open the door to developing silicon-integrated deterministic sources of photonic qubits and spin qubits interfaced with light for long-distance quantum communications in a platform adapted to large-scale nanofabrication and integration.

Considering the advanced nanotechnology based on silicon, the SILEQS project could have significant impact in quantum technologies, including quantum integrated photonics, large-scale quantum networks and solid-state hybrid quantum systems.