ONCHIPS - On-chip integration of quantum electronics and photonics
Breakthrough optoelectronics platform could create light-emitting silicon
Silicon photonics technology allows photonic components to be integrated into a tiny chip. The technology promises greater energy efficiency and lightning-speed processing but comes with a major roadblock: conventional cubic silicon has an indirect band gap, which renders it optically inactive. Unless germanium is added to silicon, in a fully new hexagonal crystal structure, silicon is not good at dealing with light. To overcome this issue, the EU-funded ONCHIPS project aims to build hexagonal germanium-silicon heterostructures for quantum technology applications and realise spin qubits in quantum dots. Furthermore, researchers will build single-photon detectors for light wavelengths exceeding 2 mm. The ONCHIPS novel platform interfacing individual spin qubits and photons could drastically enhance quantum system scalability.
A major roadblock for silicon-based optoelectronics and its quantum applications is that conventional cubic silicon has an indirect band gap, and hence it is optically inactive. ONCHIPS will capitalize on a recent breakthrough from within its consortium: growth and optical characterization of a revolutionary new material: hexagonal germanium-silicon (hex-GeSi), which is a silicon-based, optically active, direct-bandgap semiconductor. Building on this discovery, ONCHIPS' key objectives are as follows:
- We will for the first time grow advanced hex-GeSi heterostructures for quantum technology applications.
- We will realise spin qubits in quantum dots in hex-GeSi.
- We will create spin-photon interfaces in hex-GeSi, made possible by the direct bandgap of the material.
- We will build single-photon detectors for wavelengths beyond 2 micrometers, optimized for emission from hex-GeSi.
This project is well aligned with the scope of the call, and will foster the integration of electronic and optoelectronic functionalities based on a silicon-based direct-bandgap semiconductor, using a combination of facilities and expertise that is available only in Europe.
Hence ONCHIPS will establish a strong contribution to European innovation leadership in electronics, photonics, emerging enabling technologies in general, and quantum technologies in particular, making our contributions highly relevant for the work program. This new material has the potential to be compatible with standard silicon-based semiconductor technology, benefitting from established roadmaps on miniaturization and scalability.