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3D Magnetization Textures: Toroidal Magnetic Hopfion Stability in Cylindrical Samples.
Konstantin Guslienko1,2,3
1Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología, Universidad del País Vasco, UPV/EHU, 20018 San Sebastián, Spain.
Nanomaterials (Basel, Switzerland)
|January 11, 2024
Summary
Researchers found that toroidal hopfions are a stable magnetic pattern in nanostructures. This discovery in ferromagnetic materials is achieved through micromagnetism theory and external magnetic fields.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Topologically non-trivial magnetization configurations like hopfions, skyrmions, and vortices are key research areas in nanoscale ferromagnetism.
- Understanding these complex magnetic structures is crucial for developing advanced magnetic devices.
Purpose of the Study:
- To investigate the stability of toroidal hopfion magnetization configurations in nanoscale ferromagnetic materials.
- To determine the key energy contributions and interactions governing hopfion formation and stability.
Main Methods:
- Application of the theory of micromagnetism.
- Analysis of the competition between exchange, magnetostatic, and magnetic anisotropy energies.
- Consideration of Dzyaloshinskii-Moriya exchange interaction and surface magnetic anisotropy.
Main Results:
- Demonstration that the toroidal hopfion is a metastable state in thick cylindrical ferromagnetic nanodots or finite-radius nanowires.
- Identification of the interplay between exchange, magnetostatic, and anisotropy energies as the primary drivers of hopfion stability.
- Confirmation that Dzyaloshinskii-Moriya interaction and surface anisotropy play secondary roles.
Conclusions:
- The toroidal hopfion represents a stable, metastable magnetic configuration in specific ferromagnetic nanostructures.
- This magnetic state can be achieved by applying an external magnetic field along the cylindrical axis during sample remagnetization.
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