Magnetodynamical response of large-area close-packed arrays of circular dots fabricated by nanosphere lithography

We report a combined experimental and theoretical study of the quasistatic hysteresis and dynamic excitations in large-area arrays of NiFe nanodisks forming a hexagonal lattice with the lattice constant of 390 nm. Arrays were fabricated by patterning a 20-nm thick NiFe film using the etched nanosphere lithography. We have studied a close-packed and an ultraclosed packed array. Results of this systematic research are relevant both for fundamental studies of spin-wave modes in patterned magnetic structures and for the design of magnonic crystals for potential applications as, e.g., spin-wave guides and filters.