Fig. 3. Experimental demonstration of the elliptical, linear and circular polarization conversion dichroism.

a–c SEM images of the dichroism metasurfaces for different ellipticities, including (a) elliptical, (b) linear and (c) circular polarization states; the scale bar is 400 nm. The sizes (l₁, w₁, l₂, w₂) of the two nanopillars are (130 nm, 70 nm, 150 nm, 85 nm), (95 nm, 95 nm, 145 nm, 80 nm) and (160 nm, 75 nm, 165 nm, 100 nm) for a, b and c, respectively. d–i Simulated and measured transmittances of all possible polarizations covering the full Poincaré sphere through the d, e elliptical, f, g linear and h, i circular dichroism metasurfaces. The red and blue stars represent the polarization states with maximum and minimum transmittance depicted as red and blue ellipses, respectively. The dots represent the transmitted polarization states denoted as dashed ellipses. j–o Simulated and measured transmission spectra and dichroism spectra for j, k elliptical, l, m linear and n, o circular dichroism metasurfaces.