Why are physicists interested in Rydberg atoms?

Rydberg physics opens up a varied and intriguing playground for researchers. It acts like a microscope for the subtle processes of quantum physics, i.e. the physics of the smallest particles with their often-bizarre behaviour. Because of their sensitivity, Rydberg atoms are relatively easy to observe. They also strengthen interactions that would otherwise be too weak to measure. For example, they react to minimal microwave fields, i.e. the wavelengths used by mobile phones. In addition, Rydberg atoms themselves can have very unusual effects, such as one giant atom blocking the creation of another in its immediate vicinity. Hence, these exotic atoms arrange themselves into regular patterns reminiscent of mosaics.

Physicists use multiple Rydberg atoms to build models of things that they would otherwise not be able to investigate in detail. Solids, for instance: Rydberg atoms can be arranged to have the same symmetry as the atoms in a crystal. The interactions between them can be precisely controlled, as the disruptive influences of a natural solid are suppressed. They thus deliver a clean, controllable model.

Using Rydberg molecules, researchers hope to gain a better understanding of how binding partners interact in a particle network.

The playing field is becoming more and more viable for physicists, because they are developing more and more precise measuring techniques and ways to create Rydberg atoms or other exotic states using Rydberg atoms. This opens the door to a more detailed and well-founded understanding of the physics of minute particles. And new technical applications come from new knowledge.

Text: Christian Meier. Translation: Kern Group.