Investigating the trade-off between color saturation and angle-independence in photonic glasses

Photonic glasses, isotropic structures with short-range correlation, can produce structural colors when the wavelength of light is comparable to the correlation length. Experimental studies suggest it is difficult to obtain both highly saturated and angle-independent structural colors in photonic glasses without absorption. To understand why, we quantitatively analyze the trade-off between saturation and angle-dependence in photonic glasses. We take advantage of the isotropy, which allows us to express the degree of short-range order through the structure factor S(q). With this simplification, we are able to simulate multiple scattering using a Monte Carlo approach. We use the simulations to understand how varying the degree of short-range order affects the color. We show that both the color saturation and angle-independence depend primarily on the shape of the first peak of the structure factor.