Optical Trapping and Positioning of Silicon Nanowires via Photonic Nozzling

We have improved the maximum two-dimensional translationrate of optically tweezed silicon nanowires to 30 mu m/s while lowering thepower usage by an order of magnitude from the similar to 100 mW range to 6 mWusing a siliconfilm substrate at 532 nm laser wavelength. We then explain themechanism for the enhanced tweezing usingfinite difference time domainsimulation aswaveguide nozzlingof the incident radiation, directing thelight underneath the nanowire where it is confined and forced to propagateopposite to the direction of nanowire motion. We then demonstrate therobust and deterministic placement of the nanowires on the Sifilm surfaceusing a nanosecond laser at the same wavelength.

Automated summary

In this study, we have improved the maximum two-dimensional translation rate of optically tweezed silicon nanowires using a silicon film substrate and a specific laser wavelength. We have also reduced the power usage significantly. The mechanism for the enhanced tweezing effect was explained using finite difference time domain simulation, and the robust and deterministic placement of the nanowires on the film surface was demonstrated experimentally.