Distant RF field sensing with a passive Rydberg-atomic transducer

TL;DR

This paper presents a passive, remote RF sensing system using a Rydberg-atom vapor cell and optical links, enabling microwave detection at a distance without electrical components at the sensing site.

Contribution

The work introduces a novel remote RF transducer based on Rydberg atoms, allowing distant microwave sensing via optical links without local electronics.

Findings

Achieved a ~30 meter free-space optical link for RF sensing.

Demonstrated remote detection of microwave signals using a passive atomic transducer.

Showed potential for extending the sensing distance significantly.

Abstract

We combine a rubidium vapor cell with a corner-cube prism reflector to form a passive RF transducer, allowing the detection of microwave signals at a location distant from the active components required for atomic sensing. This compact transducer} has no electrical components and is optically linked to an active base station by a pair of free-space laser beams that establish an electromagnetically induced transparency scenario. Microwave signals at the transducer location are imprinted onto an optical signal which is detected at the base station. Our sensing architecture with a remote standalone transducer unit adds important flexibility to Rydberg-atom based sensing technologies, which are currently subject to significant attention. We demonstrate a \sim 30 m link with no particular effort and foresee significant future prospects of achieving a much larger separation between the transducer and the base station.