We develop an effective low-frequency theory of the electromagnetic field in equilibrium with thermal objects. The aim is to compute thermal magnetic noise spectra close to metallic microstructures. We focus on the limit where the material response is characterized by the electric conductivity. At the boundary between empty space and metallic microstructures, a large jump occurs in the dielectr...

The elements of the magneto-dipole (MD) interaction matrix are calculated for a pair oriented spheroidal magnetic nanoparticles with semiaxes ratio a/b = 1.25, 1.5, 2.0 and 3.0 as function distance between particle centers. It is shown that spherical approximation MD incorrect already at aspect ratios > if R centers order sizes. However, moderate ratios, < first correction to respect correspond...

Several second order edge elements have been applied to solving magnetostatic problems. The performances of these elements are compared through an example of magnetic circuit. In order to ensure the compatibility of the system equations and hence the convergence, the current density is represented by the curl of a source field. This avoids an explicit gauge condition which is cumbersome in the ...