Dynamics of topological defects in ion Coulomb crystals

TL;DR

This paper investigates the behavior and control of topological defects, specifically kink solitons, in two-dimensional ion Coulomb crystals through experimental and theoretical methods, highlighting how impurities and electric fields influence their dynamics.

Contribution

It demonstrates how different types of kink solitons can be realized, transformed, and manipulated in ion Coulomb crystals, including the effects of impurities and external electric fields.

Findings

Different kink types can be realized and transformed by changing trap aspect ratio.

Impurities like mass defects affect kink stability and dynamics.

Electric fields enable controlled manipulation and creation of kinks.

Abstract

We study experimentally and theoretically the properties of structural defects (kink solitons) in two-dimensional ion Coulomb crystals. We show how different types of kink solitons with different physical properties can be realized, and transformed from one type into another by varying the aspect ratio of the trap confinement. Further, we discuss how impurities in ion Coulomb crystals, such as mass defects, can modify the dynamics of kink creation and their stability. For both pure and impure crystals, the experimentally observed kink dynamics are analyzed in detail and explained theoretically by numerical simulations and calculations of the Peierls-Nabarro potential. Finally, we show that static electric fields provide a handle to vary the influence of mass defects on kinks in a controlled way and allow for deterministic manipulation and creation of kinks.