Ferromagnetic resonance study of the exchange bias field in NiFe/FeMn/NiFe trilayers

摘要

The ferromagnetic resonance (FMR) technique is used to study the exchange bias field in asymmetrical NiFe/FeMn/NiFe trilayers produced by dc magnetron sputtering under different working pressures. The FMR spectra give evidence of two resonance modes attributed to the two asymmetrical noninteracting NiFe layers. The study of the in-plane angular dependence of the absorption field allows the measurement of the exchange bias field at both bottom ferromagnetic (FM)/antiferromagnetic (AFM) and top AFM/FM interfaces.