Refractive index of ZnO ultrathin films alternated with Al2O3 in multilayer heterostructures - López-Medina, J.; Carvalho, William O. F.; Vazquez-Arce, J.; Moncada-Villa, E.; Oliveira Junior, Osvaldo Novais de; Farías, M. H.; Tiznado, H.; Mejía-Salazar, J. R. (Nanotechnology, 2020)