Analytic form of transverse head-to-head domain walls in thin cylindrical wires

作者：Hertel Riccardo^*; Kakay Attila

来源：Journal of Magnetism and Magnetic Materials, 2015, 379: 45-49.

DOI：10.1016/j.jmmm.2014.11.073

• Head-to-head domain wall
• Cylindrical magnetic nanowire
• Vertical Bloch line
• Demagnetizing factors

The static problem of a one-dimensional, transverse head-to-head domain wall structure in a thin soft magnetic nanowire with circular cross-section is treated within the framework of micromagnetic theory. An analytic form of the domain wall profile is derived, which yields that the domain wall profile depends on the wire radius. The analysis is performed by decomposing the magnetostatic energy into a monopolar and a dipolar term. We present a model in which the dipolar term of the magnetostatic energy resulting from the transverse magnetization in the center of the domain wall is calculated with Osborn's formulas for homogeneously magnetized ellipsoids [Phys. Rev. 67 (1945) 351] [22]. The analytic results agree almost perfectly with simulation data as long as the wire diameter is sufficiently small to prevent inhomogeneities of the magnetization along the cross-section. Owing to the recently demonstrated negligible Daring mass of these walls, our results should also apply to the dynamic case, where domain walls are driven by spin-transfer toque effects and/or an axial magnetic field.

• 出版日期2015-4-1