Nucleation and Stability of Toron Chains in Non-Centrosymmetric Magnetic Nanowires

Nanomaterials (Basel). 2023 Jun 7;13(12):1816. doi: 10.3390/nano13121816.

Abstract

This work analyzes the magnetic configurations of cylindrical nanowires with a bulk Dzyaloshinskii-Moriya interaction and easy-plane anisotropy. We show that this system allows the nucleation of a metastable toron chain even when no out-of-plane anisotropy exists in the nanowire's top and bottom surfaces, as usually required. The number of nucleated torons depends on the nanowire length and the strength of an external magnetic field applied to the system. The size of each toron depends on the fundamental magnetic interactions and can be controlled by external stimuli, allowing the use of these magnetic textures as information carriers or nano-oscillator elements. Our results evidence that the topology and structure of the torons yield a wide variety of behaviors, revealing the complex nature of these topological textures, which should present an exciting interaction dynamic, depending on the initial conditions.

Keywords: Bloch points; metastable states; micromagnetism; torons.

Grants and funding

We acknowledge partial financial support from BASAL/ANID under Grant AFB220001, CEDENNA. Besides this, we acknowledge financial support from ANID/FONDECYT grant number 1220215. V.L.C.-S. thanks the Brazilian agencies CNPq (Grant No. 305256/2022-0) and Fapemig (Grant No. APQ-00648-22) for financial support and Cedenna and Universidad de Santiago de Chile for hospitality.