Figure 3.

Omnidirectional coloration in scattering. a) Schematic of eNPoM metafilm and b) SEM image of film coated using meniscus‐guided assembly. Inset shows corresponding optical image. c) Simulated downward scattering (solid line) and absorption (dashed line) spectra for oxidation (green) and reduction (red) states of PANI with different Au thickness (15 nm, 10 nm, 5 nm from dark to faint lines). d) Experimental DF upward‐ (top) and downward‐scattering images (bottom) of the eNPoM metafilm with 5 nm Au thickness, and e) corresponding scattering spectra and f) coupled mode peak intensity and wavelength change versus applied voltage −0.2↔0.65V. The transparent lines indicate simulated results for oxidation (green) and reduction (red) states of PANI (solid lines correspond to upward scattering, and dashed lines are downward scattering).