Dynamics of Dielectrophoretic-Force-Directed Assembly of NaYF4 Colloidal Nanocrystals into Tunable Multilayered Micropatterns.

The dynamics of dielectrophoretic-force-directed assembly of polarizable colloidal upconverting β-NaYF4 nanocrystals into tunable multilayers on charge micropatterns written by atomic force microscopy is investigated. Multilayered nanocrystal assembly by this nanoxerography process occurs in two phases. During the first phase typically lasting a few minutes, the nanocrystal assemblies grow up to a maximum thickness under the influence of strong dielectrophoretic forces exerted by the charge patterns.