Transduction of electrically driven single photons: Surface acoustic waves meet whispering gallery mode resonators

Future quantum technologies will rely on different physical systems working together — for example, electronic quantum chips operating at very low temperatures and optical networks that can send information over long distances. A major challenge today is how to connect these systems without losing fragile quantum information in the process.

This project brings together Professor Harald Schwefel and Dr Florian Sedlmeir from the University of Otago with researchers at Kyung Hee University in South Korea to explore a new kind of quantum interface. The team will combine tiny sound waves travelling on a crystal surface — called surface acoustic waves — with ultra-pure optical resonators that trap light in small disk. By letting these sound waves and light waves interact in a controlled way, we will convert information from electrical signals into optical signals one quantum at a time.

Achieving this would be an important step towards building larger-scale quantum technologies, enabling devices that currently operate independently to work together in the same network. The long-term project vision is a versatile technology platform that can serve many future applications, from precision measurement to quantum communication systems.