Coplanar probe microwave current injection ferromagnetic resonance of magnetic nanostructures

Abstract

The non-uniform standing spin-wave modes in thin magnetic films and nanostructures provide important information about their magnetic properties. Very often they are lacking in the recorded ferromagnetic resonance spectra for symmetry reasons. In this work we experimentally demonstrate that by direct injection of microwave currents into a magnetic nanostructure using a sub-millimetre sized microwave coaxial to coplanar adaptor one can efficiently excite non-uniform standing spin wave modes with odd symmetry. The proposed method is quick and allows easy spatial mapping of magnetic properties with the resolution down to 100 μm. We have validated this method using an example from a periodical array of nanostripes. © Europhysics Letters Association.