Rydberg states with a liquid core

TL;DR

This paper introduces a self-consistent model for Rydberg electrons in polarizable liquid cores, revealing how droplet size and properties influence electron spectra and offering methods to probe droplet characteristics.

Contribution

It presents a novel explicit potential approach for Rydberg electrons in polarizable media, accounting for non-perturbative effects and droplet size dependence.

Findings

Electron spectra depend on droplet size and excitation.

Droplet polarization breaks angular momentum degeneracy.

Proposed methods to probe droplet properties via Rydberg transitions.

Abstract

We develop a self-consistent approach that provides an explicit potential for a Rydberg electron whose ionic core consists of a polarizable medium, typically realized with superfluid droplets. The electron's motion remains separable in spherical coordinates, but the radial force exerted by the droplet breaks degeneracy of the angular momentum states non-perturbatively. The ensuing electron spectrum reveals intriguing properties dependent on droplet size and electron excitation. Deviations of the polarizable medium from the continuous spherical distribution can be taken into account as a perturbation of this redefined Rydberg dynamics. We discuss specific but paradigmatic examples for superfluid helium and also propose a way to probe droplet properties including its possible crystallized fraction through stimulated transitions of the Rydberg electron.