Fig. 5: Simulated absorption characteristics of two types of Ti/Si/SiO2/Ti absorbers from long to very long infrared regime.
From: Ultra-broadband metamaterial absorbers from long to very long infrared regime
a Schematic and b absorption spectrum of the Ti/Si/SiO2/Ti absorber from 14 to 30 μm. (s1 = 1.9 μm, s2 = 0.23 μm, b1 = 0.25 μm, b2 = 1.17 μm, h1 = 0.52 μm, h2 = 1.11 μm and p = 4 μm). c Schematic and d absorption spectrum of the Ti/Si/SiO2/Ti absorber from 8 to 30 μm. (s1′ = 1.9 μm, s2′ = 0.27 μm, b1′ = 0.25 μm, b2′ = 1.21 μm, h1′ = 0.18 μm and h2′ = 1.62 μm) The thickness of the top Ti layer is 22 nm and the bottom Ti layer is 120 nm, which is thicker than its penetration depth
