Frederik L. Durhuus , Ellen Fogh , Thomas Jauho , Marco Beleggia
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引用次数: 0
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 parallel to the bottom plane and 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.
期刊介绍：
The Journal of Magnetism and Magnetic Materials provides an important forum for the disclosure and discussion of original contributions covering the whole spectrum of topics, from basic magnetism to the technology and applications of magnetic materials. The journal encourages greater interaction between the basic and applied sub-disciplines of magnetism with comprehensive review articles, in addition to full-length contributions. In addition, other categories of contributions are welcome, including Critical Focused issues, Current Perspectives and Outreach to the General Public.
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Technically original research documents that report results of value to the communities that comprise the journal audience. The link between chemical, structural and microstructural properties on the one hand and magnetic properties on the other hand are encouraged.
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The sub-section on Nanomagnetism contains articles on magnetic nanoparticles, nanowires, thin films, 2D materials and other nanoscale magnetic materials and their applications.
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