Extreme ultraviolet multilayers for solar physics applications

A review of extreme ultraviolet multilayers for solar physics applications is presented. Several promising material couples have been explored to optimize the peak reflectance at different wavelengths [1]. Ad hoc capping layers can be employed both to protect the structure underneath and to enhance the reflectance performance [2]. Such goal is achieved also by introducing an a-periodic design in the top most layers. The results are discussed also considering other features, such as spectral width and purity [3, 4]. Further improvement of related performance can be achieved by a-periodic designs, which provide novel solutions to be considered in view of future space missions. The proposed designs are discussed considering their stability in time and along space missions.