The magnetostatic field in a terahertz rod/film structure

The magnetostatic field distribution in a structure formed from a ferromagnetic (FM) rod and thin FM film is numerically calculated. The effective terahertz radiation was previously discovered in such a structure in the presence of a current. It is shown that nanodimensional sections of the boundary between the lateral surface of the rod and the surface of the film can be a source of radiation. On these sections, the magnetostatic field changes its direction, a circumstance that provides for conditions for radiative transitions of electrons.