An integrated microwave-to-optics interface for scalable quantum computing

Understand

Microwave-to-optics transduction is emerging as a vital technology for scaling quantum computers and quantum networks.

• To establish useful entanglement links between qubit processing units, several key conditions have to be simultaneously met: the transducer must add less than a single quantum of input referred noise and operate with high-efficiency, as well as large bandwidth and high repetition rate.
• Here we present a new design for an integrated transducer based on a planar superconducting resonator coupled to a silicon photonic cavity through a mechanical oscillator made of lithium niobate on silicon.
• We experimentally demonstrate its unique performance and potential for simultaneously realizing all of the above conditions, measuring added noise that is limited to a few photons, transduction efficiencies as high as 0.9%, with a bandwidth of 14.8 MHz and a repetition rate of up to 100 kHz.