Cavity electro-optics in thin-film lithium niobate for microwave-to-optical transduction

Cavity electro-optics is a promising approach to creating high efficiency, low noise, and wide bandwidth transduction between microwave and optical fields, which would enable large-scale optical networking of superconducting quantum processors. Here we present a cavity electro-optic transducer in a thin-film lithium niobate platform, which provides strong nonlinearity and low optical loss. We demonstrate on-chip photon transduction efficiency of more than 10^-5 with a bandwidth larger than 10 Mhz and characterize the impact of optical absorption in the superconducting microwave resonator on the noise and efficiency of the transducer. Finally, we describe how further development of this platform can achieve near-unity transduction efficiency with low optical pump power.