Free-Standing Photonic Glasses Fabricated in a Centrifugal Field.

One efficient method to obtain disordered colloidal packing is to reduce the stability of colloidal particles by adding electrolytes to the colloidal dispersions. But the correct amount of additional electrolytes must be found empirically. Here, the effect of CaCl on polystyrene colloidal dispersions is studied, and a link between the amount of CaCl and the corresponding glassy colloidal structure is quantitatively built.