Spin wave filtering and guiding in Permalloy/iron nanowires

•We have studied the spin wave properties in longitudinally and transversely magnetized single- and bi-layer nanowire arrays.•In the former case, filtering properties associated with the existence of allowed and forbidden frequency ranges were observed.•In the latter case, the SW dispersion is monotonic with number of modes and SW group velocity which markedly depend on the NW composition.•This study demonstrates that a proper choice of magnetic materials and layer structure represents and efficient way for tuning the dynamical properties of such periodic arrays of magnetic nano-elements. We have investigated the spin wave filtering and guiding properties of periodic array of single (Permalloy and Fe) and bi-layer (Py/Fe) nanowires (NWs) by means of Brillouin light scattering measurements and micromagnetic simulations. For all the nanowire arrays, the thickness of the layers is 10nm while all NWs have the same width of 340nm and edge-to-edge separation of 100nm. Spin wave dispersion has been measured in the Damon-Eshbach configuration for wave vector either parallel or perpendicular to the nanowire length. This study reveals the filtering property of the spin waves when the wave vector is perpendicular to the NW length, with frequency ranges where the spin wave propagation is permitted separated by frequency band gaps, and the guiding property of NW when the wave vector is oriented parallel to the NW, with spin wave modes propagating in parallel channels in the central and edge regions of the NW. The measured dispersions were well reproduced by micromagnetic simulations, which also deliver the spatial profiles for the modes at zero wave vector. To reproduce the dispersion of the modes localized close to the NW edges, uniaxial anisotropy has been introduced. In the case of Permalloy/iron NWs, the obtained results have been compared with those for a 20nm thick effective NW having average magnetic properties of the two materials.