Fig. 2
From: Engineering the Complex-Valued Constitutive Parameters of Metamaterials for Perfect Absorption
The refractive index n and extinction coefficient k of the Ag substrate and the hydrogenated amorphous silicon (α-Si:H) layer. The black (solid) line and the red (dash) line give the refractive index n 1 and extinction coefficient k 1 of Ag, respectively. The green (dot) line and the blue (dash dot) line give the refractive index n 2 and extinction coefficient k 2 of α-Si:H, respectively