Spin confinement by anisotropy modulation

• Published in: Journal of physics. D, Applied physics Applied physics, 2002-10, Vol.35 (19), p.2384-2390, Article 2384
• Main Authors: Bland, J A C, Lew, W S, Li, S P, Lopez-Diaz, L, Vaz, C A F, Natali, M, Chen, Y
• Format: Article
• Language: English
• Subjects: Applied sciences; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Interfacial magnetic properties (multilayers, magnetic quantum wells, superlattices, magnetic heterostructures); Magnetic properties and materials; Magnetic properties of surface, thin films and multilayers; Metals. Metallurgy; Physics
• ISSN: 0022-3727; 1361-6463
• DOI: 10.1088/0022-3727/35/19/309

The spin configuration in a magnet is in general a 'natural' consequence of both the intrinsic properties of the material and the sample dimensions. We demonstrate that this limitation can be overcome in a homogeneous ferromagnetic film by engineering an anisotropy contrast. Substrates with laterally modulated single-crystal and polycrystalline surface regions were used to induce selective epitaxial growth of a ferromagnetic Ni film. The resulting spatially varying magnetic anisotropy leads to regular perpendicular and in-plane magnetic domains, separated by a new type of magnetic domain wall-the 'anisotropy constrained' magnetic wall. Micromagnetic simulations indicate that the wall is asymmetric, has a small out-of-plane component and has no mobility under external perturbation. (Example material: epitaxial Cu/Ni /Cu(001).)