Eur. Phys. J. B 45, 283-288 (2005)
https://doi.org/10.1140/epjb/e2005-00174-7

Temperature dependence of ferromagnetic resonance in permalloy/NiO exchange-biased films

¹ Institute of Molecular Physics, Polish Academy of Sciences, 60-179 Poznań, Poland
² Dept. of Physics, A. Mickiewicz Univ., Umultowska 85, 61-613 Poznań, Poland
³ q-Psi and Depart. of Physics, Hanyang Univ., Seoul, 133-791 Korea
⁴ Department of Physics, Kassel Univ., H. Plett Str. 40, 34132 Kassel, Germany

Corresponding author: ^a dubowik@ifmpan.poznan.pl

Received: 2 September 2004
Revised: 9 March 2005
Published online: 28 June 2005

Abstract

The temperature dependencies of the ferromagnetic resonance (FMR) linewidth and the resonance field-shift have been investigated for NiO/NiFe exchange-biased bilayers from 78 K to 450 K. A broad maximum in the linewidth of 500 Oe, solely due to the exchange-bias, is observed at ≈150 K when the magnetic field is applied along the film plane. When the magnetic field is applied perpendicular to the film plane, the maximum in the linewidth is less pronounced and amounts to 100 Oe at the same temperature. Such a behavior of the FMR linewidth is accompanied with a monotonic increase in the negative resonance field-shift with decreasing temperature. Our results are compared with the previous experimental FMR and Brillouin light scattering data for various ferromagnetic/antiferromagnetic (FM/AF) structures, and suggest that spin dynamics (spin-wave damping and anomalous resonance field-shift) in the FM/AF structures can be described in a consistent way by a single mechanism of the so-called slow-relaxation.