Assisted convective-capillary force assembly of gold colloids in a microfluidic cell: Plasmonic properties of deterministic nanostructures

Abstract

A new colloidal assembly technique in a microfluidic cell is proposed in this work. This technique is based on classic capillary force assembly (CFA) assisted by air-suction flow and temperature control during the assembly process. Their influence on the assembly macroscopic (triple contact-line speed, receding contact angle) and microscopic (colloidal motion at the triple contact line) parameters is examined. It is shown that the extent and the performance of the assembly process are significantly enhanced by this approach. Finally, the plasmonic properties of deterministic linear (2–5 colloid long) and tripod gold nanostructures created with this technique are investigated.