Local Symmetries and Order-Disorder Transitions in Small Macroscopic Wigner Islands

TL;DR

This paper investigates how local symmetries influence the disordering process in small Wigner islands, revealing multiple transition stages driven by individual and collective excitations, and emphasizing careful analysis beyond traditional criteria.

Contribution

It provides a detailed analysis of the disordering transitions in small Wigner islands, highlighting the role of local symmetries and differentiating between individual and collective excitations.

Findings

First disordering step linked to local symmetries

Identification of orthoradial and radial diffusion transitions

Caution against overreliance on Lindemann criterion for small systems

Abstract

The influence of local order on the disordering scenario of small Wigner islands is discussed. A first disordering step is put in evidence by the time correlation functions and is linked to individual excitations resulting in configuration transitions, which are very sensitive to the local symmetries. This is followed by two other transitions, corresponding to orthoradial and radial diffusion, for which both individual and collective excitations play a significant role. Finally, we show that, contrary to large systems, the focus that is commonly made on collective excitations for such small systems through the Lindemann criterion has to be made carefully in order to clearly identify the relative contributions in the whole disordering process.