Resonant soft-x-ray inelastic scattering from Gd in the Gd₃Ga₅O₁₂ garnet with excitation across the M₅ edge

We present resonant soft-x-ray scattering measurements across the M₅ edge of Gd in Gd₃Ga₅O₁₂. Below or near the Gd M₅ edge the scattering is dominated by the elastic contribution, whereas the inelastic contribution becomes dominant above the edge. The theoretical cross section is calculated in an ionic multiplet model, and the spectra are simulated by including self-absorption and saturation effects. The calculations account for all the measured features. It is shown that the inelastic contributions to the spectra are due to 4f spin-flip excitations, bringing Gd to a lower spin state in the final state.