Optomechanical ground-state cooling in a continuous and efficient electro-optic transducer

TL;DR

This paper demonstrates a highly efficient electro-optomechanical transducer that operates continuously with the mechanical mode cooled to its quantum ground state, achieving low noise and high efficiency for quantum microwave-optical conversion.

Contribution

It introduces a novel transducer design that maintains ground-state cooling and high efficiency under continuous operation, overcoming previous noise and thermal occupation challenges.

Findings

Maximum efficiency of 47% achieved

Minimum added noise of 3.2 photons in upconversion

Thermal occupancy minimally affected by high laser power

Abstract

The demonstration of a quantum link between microwave and optical frequencies would be an important step towards the realization of a quantum network of superconducting processors. A major impediment to quantum electro-optic transduction in all platforms explored to date is noise added by thermal occupation of modes involved in the transduction process, and it has proved difficult to realize low thermal occupancy concurrently with other desirable features like high duty cycle and high efficiency. In this work, we present an efficient and continuously operating electro-optomechanical transducer whose mechanical mode has been optically sideband-cooled to its quantum ground state. The transducer achieves a maximum efficiency of 47% and minimum input-referred added noise of 3.2 photons in upconversion. Moreover, the thermal occupancy of the transducer's microwave mode is minimally affected by continuous laser illumination with power more than two orders of magnitude greater than that required for optomechanical ground-state cooling.