Investigation of the properties of a 3-level broadband antireflective structure on silicon by THz time-domain spectroscopyI.A. Tzibizov, G.I. Kropotov, V.S. Pavelyev, K.N. Tukmakov and A.S. ReshetnikovEPJ Web Conf., 195 (2018) 06016DOI: https://doi.org/10.1051/epjconf/201819506016