Configurable multiband microwave absorption states prepared by field cycling in arrays of magnetic nanowires

Arrays of low diameter bi-stable electrodeposited magnetic nanowires demagnetized in the direction parallel to the wires are used to prepare non-saturated stable magnetic states formed by groups of wires magnetized positive and negative with respect to the applied field. Exploiting the coercive field distribution, both the number of wires in each group as well as the number of different groups can be varied by changing the demagnetizing cycle parameters. The ferromagnetic resonance field and peak intensity are shown to be different for each of these magnetic states. By applying demagnetizing cycles, it is possible to induce multiple absorption peaks, and thus show field-programmable multiband absorption properties.