Work

Demagnetization factors and field of hemispherical objects

Year: 2025

Type: article

Abstract: Demagnetization factors play an important role in micromagnetics modeling but exact solutions only exist for a limited number of particle shapes. Here we use a Fourier space based approach coupled to the concept of magnetic charges to derive analytically the demagnetization factors for shapes that are subsets of a sphere: spherical sectors and spherical caps . For the uniformly magnetized hemisphere, which is a special case of both geometries, the exact demagnetization factors are shown to be N x = N y = 7 / ( 9 π ) parallel to the bottom plane and N z = 1 − 14 / ( 9 π ) in the direction of the dome. Additionally, we provide expressions for shape amplitudes and demagnetization fields of these objects in terms of rapidly converging series. Our work demonstrates the potential of evaluating shape amplitudes to determine demagnetization factors in certain geometries and our results may facilitate numerical simulations of, for example, ferromagnetic droplets.

Source: Journal of Magnetism and Magnetic Materials

DOI: 10.1016/j.jmmm.2025.173047

Authors: Frederik L. Durhuus, Ellen Fogh, Thomas Jauho, Marco Beleggia

Institutions: Technical University of Denmark, École Polytechnique Fédérale de Lausanne, University of Modena and Reggio Emilia

Language: English

Topic: Magnetic Properties and Applications

Subfield: Electronic, Optical and Magnetic Materials

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,210

Funder: Danmarks Tekniske Universitet