Figure 4
From: Tunable mid-infrared coherent perfect absorption in a graphene meta-surface
Geometric tunability of the graphene meta-surface CPA: Spectra of the difference 
of the scattering coefficients (r and t) for the graphene meta-surface width increasing from 0.075 μm to 0.42 μm.
The solid line indicates quasi-CPA points where 
, while the spheres represent the extracted surface conductivities with values 
.
