The design of broad band anti-reflection coatings for solar cell applicationsAngirekula Siva Rama Krishna, Samrat Lagnajeet Sabat and Mamidipudi Ghanashyam KrishnaEur. Phys. J. Appl. Phys., 77 1 (2017) 10301DOI: https://doi.org/10.1051/epjap/2017160376