Accurate control of individual metallic nanowires by light-induced dielectrophoresis: Size-based separation and array-spacing regulation

In this paper, we utilize the light-induced dielectrophoretic technique to realize the accurate control of nanowires, including positioning of single nanowires, separation of different-sized nanowires, and spacing regulation of uniform nanowire-arrays. Nanowires can exactly stabilize at the center of a regular geometric light-spot with a slight eccentricity of 2.1 ± 0.64%. Additionally, nanowires of different lengths (∼6 μm and ∼12 μm) are separated individually by a light-bar with a proper traveling velocity, which is measured and selected according to an acceleration-displacement measurement method. Based on this, uniform nanowire-arrays are assembled instantly, and emerge an equidistant distribution. In reality, the array spacing-distance presents a frequency dependence, and can be automatically adjusted from 6 to 21 μm for two-wire array and 7-16 μm for three-wire array, respectively. The accurate positioning and orderly management of nanowires may potentially increase the efficiency of nanowire assembly, and be contributed to the nano-device building.