Dynamic manipulation and separation of individual semiconducting and metallic nanowires

Nat Photonics. 2008;2(2):86-89. doi: 10.1038/nphoton.2007.277.

Abstract

The synthesis of nanowires has advanced in the last decade to a point where a vast range of insulating, semiconducting, and metallic materials1 are available for use in integrated, heterogeneous optoelectronic devices at nanometer scales 2. However, a persistent challenge has been the development of a general strategy for the manipulation of individual nanowires with arbitrary composition. Here we report that individual semiconducting and metallic nanowires with diameters below 20 nm, are addressable with forces generated by optoelectronic tweezers (OET) 3. Using 100,000x less optical power density than optical tweezers, OET is capable of transporting individual nanowires with speeds 4x larger than maximum speeds achieved by optical tweezers. A real-time array of silver nanowires is formed using photopatterned virtual-electrodes, demonstrating the potential for massively parallel assemblies. Furthermore, OET enables the separation of semiconducting and metallic nanowires, suggesting a broad range of applications for the separation and heterogenous integration of one-dimensional nanoscale materials.