Concepedia

Digital communication with Rydberg atoms and amplitude-modulated microwave fields

Unknown author(s)

Applied Physics Letters · 2018 · 241 citations · 30 references

Open access

TL;DR

Rydberg atoms are highly sensitive to electric fields, including microwave fields from 100 MHz to over 1 THz. The study demonstrates that room‑temperature Rydberg atoms can serve as sensitive, high‑bandwidth microwave communication antennas, offering potential advantages over classical receivers. The authors achieve near photon‑shot‑noise limited readout of amplitude‑modulated 17 GHz microwaves via an electromagnetically‑induced‑transparency probing scheme. They report a photon‑shot‑noise limited channel capacity of up to 8.2 Mbit/s, successfully implement an 8‑state phase‑shift‑keying protocol, and find that the EIT probing bandwidth is constrained by coupling‑laser power and the rubidium D2 natural linewidth.

Abstract

Rydberg atoms, with one highly-excited, nearly-ionized electron, have extreme sensitivity to electric fields, including microwave fields ranging from 100 MHz to over 1 THz. Here we show that room-temperature Rydberg atoms can be used as sensitive, high bandwidth, microwave communication antennas. We demonstrate near photon-shot-noise limited readout of data encoded in amplitude-modulated 17 GHz microwaves, using an electromagnetically-induced-transparency (EIT) probing scheme. We measure a photon-shot-noise limited channel capacity of up to 8.2 Mbit/s and implement an 8-state phase-shift-keying digital communication protocol. The bandwidth of the EIT probing scheme is found to be limited by the available coupling laser power and the natural linewidth of the rubidium D2 transition. We discuss how atomic communications receivers offer several opportunities to surpass the capabilities of classical antennas.