Defect engineering in sedimentary colloidal crystals to produce photonic crystals

In this paper, lithographic methods are successfully employed to create growth templates for colloidal self-assembly, enabling the inclusion of crystallographic defects at predetermined positions. It is shown that through smart template design stacking faults can be grown predictably into face centered cubic structures. More interestingly, by precise guiding of the stacking faults hollow intergrowth channels can be grown at predetermined lateral and vertical positions. The mechanisms involved in defect growth are promising for extension of this technique to more complex crystal structures, such as the diamond structure, as well as to more complex faults, including corners and t-junctions.