Propagating Quantum Microwaves: Towards Applications in Communication and Sensing

TL;DR

This paper reviews recent advances in propagating quantum microwaves, highlighting challenges and future directions in quantum communication and sensing applications, including secure communication and dark matter detection.

Contribution

It provides a comprehensive overview of the state-of-the-art in quantum microwave propagation, proposing new ideas and identifying challenges for future research in the field.

Findings

Progress in microwave-to-optical platforms for secure communication

Potential applications in quantum sensing and dark matter detection

Identification of technical and theoretical challenges

Abstract

The field of propagating quantum microwaves has started to receive considerable attention in the past few years. Motivated at first by the lack of an efficient microwave-to-optical platform that could solve the issue of secure communication between remote superconducting chips, current efforts are starting to reach other areas, from quantum communications to sensing. Here, we attempt at giving a state-of-the-art view of the two, pointing at some of the technical and theoretical challenges we need to address, and while providing some novel ideas and directions for future research. Hence, the goal of this paper is to provide a bigger picture, and -- we hope -- to inspire new ideas in quantum communications and sensing: from open-air microwave quantum key distribution to direct detection of dark matter, we expect that the recent efforts and results in quantum microwaves will soon attract a wider audience, not only in the academic community, but also in an industrial environment.