X-ray polarization: General formalism and polarization analysis

The polarization of X-rays plays an outstanding role in experimental techniques such as non-resonant magnetic X-ray scattering and resonant X-ray scattering of magnetic and multipolar order. Different instrumental methods applied to synchrotron light can transform its natural polarization into an arbitrary polarization state. Several synchrotron applications, in particular in the field of magnetic and resonant scattering rely on the improvement in the signal/noise ratio or the deeper insight into the ordered state and the scattering process made possible through these polarization techniques. Here, we present the mathematical framework for the description of fully and partially polarized X-rays, with some applications such as linear X-ray polarization analysis for the determination of the scattered beam's polarization, and the Ge K-edge resonant scattering.