کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1800198 | 1524886 | 2013 | 8 صفحه PDF | دانلود رایگان |
The high frequency magnetic susceptibility of glass-coated microwires with effective circumferential anisotropy has been modeled by micromagnetics. In their amorphous and magnetically soft metallic nucleus, the negative magnetostriction induces a continuous and non-uniform vortex-like structure, with an axially magnetized core coupled to a circumferentially magnetized outer shell. The model is a one-dimensional radial micromagnetic model where exchange, magnetoelastic and magnetostatic energies are considered. The microwave permeability under AC (axial and circumferential) fields is found to be expressed as a sum over a set of eigenmodes, each with a characteristic resonance frequency. In the framework of this model, a sum rule on the frequency-dependent permeability is shown to hold. It provides a figure of merit and guidelines for the design of high permeability materials for applications in the microwave range.
► We model the magnetization dynamics for microwires with non-uniform structure.
► The microwave response depends on radius, exchange, anisotropy and external fields.
► The permeability spectra are computed as the sum of radial spin waves.
► Both axial and circumferential AC field orientations are considered.
► The permeability level and resonance peak are different from macrospin predictions.
Journal: Journal of Magnetism and Magnetic Materials - Volume 333, May 2013, Pages 144–151