Reflection of soft X rays from quasi-periodic multilayer films

摘要

Abstract: A quasi-periodic design method for soft x-ray multilayer reflector to achieve high reflectivity and low loss is presented. The dependence of the reflectivity on the optical constants of the absorbing layers for a given substrate and spacer materials is investigated, and the criterion of choosing optical components is also discussed. We find that when the extinction coefficient of the absorber is large, the reflectivity of the multilayer reflector is governed by the difference of the extinction coefficients of the components. In order to obtain high reflectivity in the case of large extinction coefficient, one should choose a pair of materials with large difference of extinction coefficients.!8