Pillar 3: Optical Manipulation of Microwave Photons
Light carries momentum—it can literally “push” on matter. Trapped light in a resonator gives a delayed push to a mechanical element, producing feedback that can cool motion (damping) or drive it (anti-damping). Cavity electro-optics uses the same idea but links an optical cavity to a microwave resonator through a material whose optical properties change with voltage. By tuning the optical frequency and power, scientists can cool microwave modes, amplify them into self-oscillation, or convert microwave quantum signals into optical ones. Those capabilities could help scale up superconducting quantum processors and link them over long distances.
The Goal
To make the interaction between light and microwaves as efficient as possible. For this the CIELO team has been developing the optical and microwave subsystems so that the “boring” photon loss processes happen very slowly, while the “interesting” electro-optic interactions can have sufficient time to unfold.
Year 1 Achievements
The CIELO team has been developing the optical and microwave subsystems so that the “boring” photon loss processes happen very slowly, while the “interesting” electro-optic interactions can have sufficient time to unfold. Through clever design, the microwave and optical modes are made very small and placed in the same tiny region. As the same energy is squeezed into less space, the intrinsic fluctuations of the electric fields become much stronger. As a result, each microwave oscillation has a larger effect on the light, and the light pushes back more effectively on the microwave. These effects will soon be characterized. (EPFL)