High efficiency coherent microwave-to-optics conversion via off-resonant scattering

TL;DR

This paper demonstrates a highly efficient microwave-to-optics quantum transducer using Rydberg atoms and off-resonant scattering, achieving 82% efficiency without cavities or extreme cooling, suitable for quantum technologies.

Contribution

It introduces a novel off-resonant scattering technique with Rydberg atoms for microwave-to-optics conversion, surpassing previous efficiency limits and simplifying the setup.

Findings

Achieved 82% conversion efficiency

Operates over a bandwidth of about 1 MHz

Effective for microwave photons from thousands to 50

Abstract

Quantum transducers that can convert quantum signals from the microwave to the optical domain are a crucial optical interface for quantum information technology. Coherent microwave-to-optics conversions have been realized with various physical platforms, but all of them are limited to low efficiencies of less than 50\%, the threshold of the no-cloning quantum regime. Here we report a coherent microwave-to-optics transduction using Rydberg atoms and off-resonant scattering technique with an efficiency of $82\pm 2\%$ and a bandwidth of about 1 MHz. The high conversion efficiency is maintained for microwave photons range from thousands to about 50, suggesting that our transduction is readily applicable to the single-photon level. Without requiring cavities or aggressive cooling to quantum ground states, our results would push atomic transducers closer to practical applications in quantum technologies.