Anisotropy-induced Inhomogeneous Melting in Finite Dust Clusters

TL;DR

This study provides experimental evidence that anisotropic confinement causes inhomogeneous melting in finite dusty plasma crystals, with mode coupling and laser heating playing key roles.

Contribution

First experimental demonstration of anisotropy-induced inhomogeneous melting in dusty plasma crystals, highlighting the role of geometric confinement and mode interactions.

Findings

Melting patterns depend on confinement anisotropy.

Laser heating redistributes energy into specific collective modes.

Simulations confirm the role of mode coupling in melting dynamics.

Abstract

We present the first experimental evidence of inhomogeneous melting in a finite dusty plasma crystal confined in an anisotropic potential well. By systematically tuning the confinement anisotropy and applying controlled laser heating, distinct melting patterns are observed. Spectral-mode analysis based on Singular Value Decomposition of particle trajectories reveals that increasing laser power redistributes energy into specific collective modes, triggering localized structural destabilization. Molecular Dynamics simulations reproduce the observations and show that confinement-controlled mode coupling with laser heating governs the melting dynamics. These results establish geometric anisotropy as a key control parameter for inhomogeneous melting in finite coupled systems.