FMR studies of single permalloy layers sandwiched by Au

Results of FMR studies performed at X-band on two series of thin permalloy (Py) layers sandwiched by Au are reported and analyzed. These two series are characterized by an Au layer thickness of 12 and 6 nm, respectively. The FMR results are compared to the ones obtained for a series of (Py/Al2O3) control films. A strong interfacial increase of the intrinsic damping is revealed. The spin-orbit perpendicular anisotropy field is also dominated by the metallic interface contribution. Remarkable phenomena evidenced in the angular variation of the FMR spectrum may be well understood in terms of the theoretical description we have developed of the observable signal in a bimetallic (ferro/normal) film. (c) 2006 Elsevier B.V. All rights reserved.