Mechanically mediated microwave frequency conversion in the quantum regime

TL;DR

This paper demonstrates a highly efficient, low-noise microwave frequency converter using mechanical resonators, enabling quantum state transfer and photon routing in quantum networks.

Contribution

It presents the first demonstration of coherent, low-noise microwave frequency conversion mediated by mechanical motion suitable for quantum applications.

Findings

Achieved >10^{12} photons/sec conversion rate

95% conversion efficiency with 14 kHz bandwidth

Added noise below 0.1 photons per second per Hz

Abstract

We report the observation of efficient and low-noise frequency conversion between two microwave modes, mediated by the motion of a mechanical resonator subjected to radiation pressure. We achieve coherent conversion of more than $10^{12}~\mathrm{photons/s}$ with a $95\mathrm{\%}$ efficiency and a $14~\mathrm{kHz}$ bandwidth. With less than $10^{-1}~\mathrm{photons \cdot s^{-1}\cdot Hz^{-1}}$ of added noise, this optomechanical frequency converter is suitable for quantum state transduction. We show the ability to operate this converter as a tunable beam splitter, with direct applications for photon routing and communication through complex quantum networks.