Understanding how the degree of disorder affects structural colors of colloidal packings

Disordered structures that multiply scatter light sometimes show phenomena such as Anderson localization, structural colors, and super whiteness. We investigate the scattering from dense packings of spherical colloidal particles in a weak multiple scattering region. Using a Monte Carlo framework, we predict the wavelength-dependent reflectance (colors) of simulated packings. To quantify the degree of disorder, we calculate the structure factor. We then explore how variations in the structure factor affect both the reflectance and the angle-dependence of the colors. We find only the first peak of the structure factor determines the feature of the reflectance, which provide guidance to control colloidal packings to tune the colors.