Finite-element dynamic-matrix approach for spin-wave dispersions in magnonic waveguides with arbitrary cross section

We present a numerical approach to efficiently calculate spin-wave dispersions and spatial mode profiles in magnetic waveguides of arbitrarily shaped cross section with any non-collinear equilibrium magnetization that is translationally invariant along the waveguide. Our method based on propagating-wave dynamic-matrix by Henry et al. (Ref. 19) extends it arbitrary sections using finite-element method. solve linearized equation motion only single waveguide section, which drastically reduces computational effort compared common three-dimensional micromagnetic simulations. In order numerically obtain dipolar potential individual modes, we plane-wave version hybrid finite-element/boundary-element Fredkin Koehler extend modified Poisson equation. applied several important examples magnonic including systems surface curvature, such as nanotubes, where curvature leads an asymmetric dispersion. all cases, validity our confirmed other methods. particular interest for study curvature-induced or magnetochiral effects transport also serves efficient tool investigate standard problems.