Radiative damping in wave guide based FMR measured via analysis of perpendicular standing spin waves in sputtered Permalloy films

Published: November 17, 2015

Author(s)

Thomas J. Silva, Justin M. Shaw, Hans T. Nembach, Mathias Weiler, Martin Schoen

Abstract

The damping α of the spinwave resonances in 75 nm, 120 nm, and 200 nm -thick Permalloy films is measured via vector-network- analyzer ferromagnetic-resonance (VNA-FMR). Inductive coupling between the sample and the waveguide leads to an additional radiative damping term. The radiative contribution to the over-all damping is determined by measuring perpendicular standing spin waves (PSSWs) in the Permalloy films, and the results are compared to a simple analytical model. The damping of the PSSWs can be fully explained by three contributions to the damping: The intrinsic damping, the eddy-current damping, and the radiative damping. No other contributions were observed. Furthermore, a method to determine the radiative damping in FMR measurements with a single resonance is suggested.
Citation: Journal of Applied Physics
Volume: 92
Pub Type: Journals
Created November 17, 2015, Updated November 10, 2018