- A ferromagnetic resonance study of Fe/MnAs bilayers: magnetic anisotropies and interlayer coupling.

G. ALEJANDRO, MILANO J., GAYONE J.E., STEREN L.B., EDDRIEF M. , ETGENS V.H,

Buenos Aires

Conferencia; V At the Frontiers of Condensed Matter; 2010

In this work we present a ferromagnetic resonance (FMR) study of Fe/MnAs bilayers epitaxially grown on GaAs(100). Important Fe/MnAs interface effects are observed, i.e. a very weak exchange coupling between Fe and MnAs, and the addition of uniaxial anisotropy terms to the free energy density of the iron layer. Moreover, the general appearance of the FMR iron spectrum is highly temperature dependent.  The resonance field, line-width and the intensity of the Fe line are strongly altered in the alpha-beta phase coexistence region of the MnAs layer, where a severe drop of the resonance field is simultaneously observed. A complementary chemical profile analysis of the sample shows an important intermixing at the Fe/MnAs interface, which arises as a crucial factor for the understanding of the magnetic behaviour of this system.