Wigner lattice of ripplopolarons in a multielectron bubble in helium

TL;DR

This paper investigates ripplopolarons in multielectron helium bubbles, predicting a Wigner crystal phase formed by electron-induced surface dimples, with specific conditions for its realization and a unique melting mechanism involving ripplopolarons dissociation.

Contribution

It introduces a theoretical framework for ripplopolaron Wigner crystallization in helium bubbles and identifies conditions for phase stability and melting.

Findings

Wigner crystal of ripplopolarons can form under certain conditions.

The phase melts via ripplopolarons dissociation when pressure drops.

Derived experimental parameters for observing this phase.

Abstract

The properties of ripplonic polarons in a multielectron bubble in liquid helium are investigated on the basis of a path-integral variational method. We find that the two-dimensional electron gas can form deep dimples in the helium surface, or ripplopolarons, to solidify as a Wigner crystal. We derive the experimental conditions of temperature, pressure and number of electrons in the bubble for this phase to be realized. This predicted state is distinct from the usual Wigner lattice of electrons, in that it melts by the dissociation of the ripplopolarons, when the electrons shed their localizing dimple as the pressure on the multielectron bubble drops below a critical value.