E1 and E2 contributions to the L3 resonance line shape in antiferromagnetic holmium

A detailed study of the angular, energy and polarization dependences of the electric dipolar (E1: 2p -> 5d) and quadrupolar (E2: 2p -> 4f) contributions to the x-ray scattering cross-section is presented for holmium in its basal plane spiral antiferromagnetic phase at the L-3 edge. The corresponding E1 and E2 scattering factors have been extracted from fits to the experimental energy line shapes, taking into account for the first time a split dipole resonance. Using the imaginary part of the resonant scattering factors to retrieve the XMCD spectrum, we find qualitative agreement with the dichroic spectrum measured in transmission through a holmium foil.