Epitaxial assembly and ordering of two-dimensional colloidal crystals

An epitaxial assembly method is described to direct the crystallization of two-dimensional colloidal crystals under an alternating electric field (AEF). By using a colloidal line as an epitaxial template, the colloidal crystals with a predefined orientation have been assembled at specified position of an electrode. The epitaxial correlation between the colloidal crystals and the template can be tuned by varying the frequency of the AEF. By control of the template and the frequency, well-defined linear defects have been incorporated into the colloidal crystals, whereas the unwanted defects can be in situ eliminated through a template-guided annealing process.