Orbital Magnetism and Magnetic Anisotropy Probed with Ferromagnetic Resonance

Via ferromagnetic resonance both the magnetic anisotropy energy (MAE) and the spectroscopic splitting tensor ( g tensor) for a bcc Fe₂/V₅(001) superlattice are measured independently. The theoretically proposed proportionality between the anisotropy of the orbital moment μL and the MAE is quantitatively checked and its limitations are discussed. From layer-resolved first-principles calculations we find a reduced spin moment μS0ex0ex=0ex0ex1.62μB for Fe and μSV0ex0ex=0ex0ex-0.67μB in the first V layer. The g-tensor elements reveal a $300%$ enhanced ratio μL/μS0ex0ex=0ex0ex0.133 in comparison to bulk Fe. The MAE and the orbital moment anisotropy is found to be unusually small for Fe monolayers.