Healing of topological defects while crystallizing nanocrystals

TL;DR

This study uses Langevin dynamics simulations to analyze how confinement influences the crystallization and defect healing in vortex nanocrystals, aligning with experimental observations.

Contribution

It provides new insights into the healing of topological defects during nanocrystal crystallization under confinement, supported by simulation and experimental data.

Findings

Healing effect at edges matches experimental data

Radial distribution of defects is stationary below melting line

Confinement influences defect profiles and vortex structure

Abstract

Understanding the role of confinement while crystallizing nanocrystals is very relevant for predicting their structure and physical properties. With this aim we perform Langevin dynamics simulations of nanocrystals of the model system of few hundred vortices nucleated in micron-sized superconductors. We study the crystallization dynamics and the low-temperature structural properties of vortex nanocrystals nucleated in field-cooling conditions when changing vortex density or elasticity of the system and physical size of the samples. The low-temperature snapshots obtained in simulations present a healing effect at the edges that is in quantitative agreement with experimental data in Bi2Sr2CaCu2O8+{\delta} micron-sized samples. We show that the low-temperature radial distribution of topological defects is a stationary profile frozen at a temperature below the melting line tuned by intrinsic properties of the vortex structure and on the confinement effect. These findings on the dynamics and spatial profile of topological defects can be applied to describe the physical properties of confined soft condensed matter nanocrystals in general.