Figure 4:

Experimental realization of a BA₂PbI₄ nanograting metasurface with dynamic color switching.

(A) SEM image of a BA₂PbI₄ nanograting metasurface patterned by nanoimprint lithography. (B and E) Experimental x-polarized and y-polarized reflection spectra at, respectively, 293 and 240 K. The insets show the reflected color recorded by a CCD. (D) Reconstructed reflected colors of the metasurface in the color space based on the simulated reflection spectra for both polarizations at (C) 293 K and (F) 240 K.