Coplanar probe microwave current injection ferromagnetic resonance of magnetic nanostructures

¹ School of Physics M013, University of Western Australia - 35 Stirling Hwy, 6009 Crawley, Australia
² Department of Electrical and Computer Engineering, National University of Singapore - 117576, Singapore
³ Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 CNRS- Université de Strasbourg 67034 Strasbourg, France, EU

^a kostylev@cyllene.uwa.edu.au

Received: 30 June 2011
Accepted: 17 October 2011

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.