Anisotropic x-ray magnetic linear dichroism at the Fe L_2,3 edges in Fe₃O₄

X-ray magnetic linear dichroism at the Fe L_2,3 edges of the ferrimagnet Fe₃O₄ was found to exhibit a strong dependence on the relative orientation of external magnetic field, x-ray polarization, and crystalline axes. Spectral shape and magnitude of the effect were determined for Fe₃O₄(011) and Fe₃O₄(001) thin films, varying the in-plane orientation of field and polarization. All dichroism spectra can be described as a linear combination of two fundamental spectra which in turn gives a good agreement with calculated spectra, using atomic multiplet theory. The angular dependence of the magnetic dichroism reflects the cubic crystal field symmetry. It can be used to estimate the crystal field splitting and allows the determination of the spin quantization axis.