This atom-based receiver has the potential to be smaller and work better in noisy environments than conventional radio receivers, among other possible advantages.
Cesium atoms were used to receive digital bits (1s and 0s) in the most common communications format of phase shifting or phase modulation. Here, radio signals or other electromagnetic waves are shifted (modulated) relative to one another over time and the information (or data) is encoded in this modulation.
"The point is to demonstrate that one can use atoms to receive modulated signals," project leader Chris Holloway said. "The method works across a huge range of frequencies. The data rates are not yet the fastest out there, but there are other benefits here, like it may work better than conventional systems in noisy environments."
In their paper, the team described a quantum sensor that received signals based on real-world phase-shifting methods. A 19.6 GHz transmission frequency was chosen because it was convenient for the experiment, but it also could be used in future wireless communications systems, Holloway said.
The NIST team previously used the same basic technique for imaging and measurement applications. Researchers use two different color lasers to prepare atoms contained in a vapour cell into high-energy ("Rydberg") states, which have novel properties such as extreme sensitivity to electromagnetic fields. The frequency of an electric field signal affects the colours of light absorbed by the atoms.
