Spin-Wave Diffraction by a Twisted Magnetic Domain Wall

We present a theoretical study of the scattering of spin waves by a twisted domain wall (DW) in a two-dimensional ferromagnet with easy-axis anisotropy. We demonstrate that the twisted DW generates an effective gauge field for spin waves—an emergent field arising from the spatial variation of the magnetization—which leads to a deflection of spin waves. In addition, we show that in the presence of hard-axis anisotropy in addition to the easy-axis anisotropy, the translational symmetry of the spin wave Hamiltonian is broken along the DW, imposing a periodic structure to the Hamiltonian. This periodicity leads to the formation of multiple diffracted spin wave modes on both sides of the DW, leading to the formation of a magnonic diffraction pattern. The interplay between the emergent gauge field and the anisotropy-induced periodicity reveals rich spin-wave dynamics and suggests potential applications for manipulating magnon flow in two-dimensional magnetic textures.