Further development of inversion technique for the analysis of X-ray and neutron reflectivity data

Analysis of X-ray and neutron reflectivity is usually done by modeling the scattering length density profile (such as multilayers) of the sample and performing a least square fit to the measured, phaseless reflectivity data. Professor T. Salditt (Institute for X-ray Physics, Universitat Gottingen) and his colleague recently attempted to extend the inversion technique. The research group discussed conditions for uniqueness, which are applicable in the kinematic limit (Born approximation), and for the most relevant case of box model profiles with Gaussian roughness. They also demonstrated that an iterative method to reconstruct the profile based on regularization works well. For more information, see the paper, "Iterative reconstruction of a refractive-index profile from x-ray or neutron reflectivity measurements", T. Hohage et al., Phys. Rev. E77, 051604 (2008).