Magnetization ground state and reversal modes of magnetic nanotori

TL;DR

This study uses micromagnetic simulations to analyze the magnetic ground states and reversal behaviors of toroidal nanomagnets, revealing geometry-dependent vortex and rotation modes with implications for data storage density.

Contribution

It provides new insights into the magnetic ground states and reversal modes of nanotori, highlighting their advantages over cylindrical nanorings for data storage.

Findings

Toroidal nanomagnets exhibit vortex and coherent rotation reversal modes.

Nanotori can host vortex ground states at smaller volumes than cylindrical nanorings.

Potential for higher data storage density using nanotori as magnetic bits.

Abstract

In this work, and by means of micromagnetic simulations, we study the magnetic properties of toroidal nanomagnets. The magnetization ground state for different values of the aspect ratio between the toroidal and polar radii of the nanotorus has been obtained. The hysteresis curves are also obtained, evidencing the existence of two reversal modes depending on the geometry: a vortex mode and a coherent rotation. A comparison between toroidal and cylindrical nanoparticles has been performed evidencing that nanotori can accommodate a vortex as the ground state for smaller volume than cylindrical nanorings. This is important because if vortices are used as bits of information, nanotori allow a higher density data storage.