Fig. 5
a Calculated absorption contour for the proposed nanohole array-based absorber as a function of the wavelength and the spacer layer thickness h2. The black dashed line represents the FP resonance and the white dashed line represents the VP mode. The inset shows the images (the dash rectangles) of the top metal layer with respect to the mirror metal interface (the white dash line). b Calculated absorption of the proposed nanohole array-based absorber dependent on h1 changing from 10 to 30 nm. c Calculated absorption contour for the proposed nanohole array-based absorber as a function of w with p = 200 nm. d Calculated absorption contour for the proposed nanohole array-based absorber as a function of p with w = 60 nm