Patent ID: 6797057
Filing Date: 2004-09-28
Classification: B82Y,C30B,G02B

Abstract:
A method of growing an essentially perfect colloidal photonic crystal exhibiting a single face-centred-cubic structure comprising the steps of:i. preparing a suspension of monosized colloidal spheres (1) having a volume concentration that produces spontaneous local crystallisation in a suitable dispersion medium, ii. inserting the colloidal suspension into a gap between two substantially parallel surfaces (2,3), iii. subjecting the surfaces to relative oscillating motion (5) parallel to their surfaces and, iv. subjecting the surfaces to a series of small linear displacements (6) relative to each other, the displacements being parallel to their surfaces and in two dimensions, comprising the sequence of applying a linear displacement to one of the surfaces with respect to the other surface, rotating the direction in which the linear displacement is applied to the surface by substantially 120 degrees in a single constant direction and applying a further linear displacement to the surface, the sequence being repeated until the colloidal photonic crystal has been purified into a single face-centred-cubic structure.