Bloch Point Structure in a Magnetic Nanosphere

TL;DR

This paper investigates the structure and stability of Bloch points in magnetic nanospheres, classifying their types, deriving their magnetization profiles analytically, and demonstrating stabilization via external gradient fields with simulation validation.

Contribution

It provides a comprehensive classification of Bloch point types, analytical magnetization profiles, and shows how external gradient fields can stabilize these singularities in nanospheres.

Findings

External gradient fields stabilize Bloch points.

Analytical magnetization profiles match spin-lattice simulations.

Identified multiple types of Bloch points in nanospheres.

Abstract

The micromagnetic singularity, the so-called Bloch point, can form a metastable state in the nanosphere. We classify possible types of Bloch points and derive analytically the shape of magnetization distribution inside different Bloch point. We show that external gradient field can stabilize the Bloch point: the shape of the Bloch point becomes radial-dependent one and compute the magnetization structure of the nanosphere, which is in a good agrement with performed spin-lattice simulations.