Nonlinear Nanowires

Project Summary

Potassium niobate (KNbO3) belongs to a unique class of materials with efficient nonlinear optical properties. That is, potassium niobate is able to convert low frequency/energy light to high frequency/energy light (for example, converting red light to blue light). Previous research has been done using laser tweezers to trap potassium niobate nanowires to use those nanowires as optical probes for biological/cellular studies.

In this project, we synthesized potassium niobate nanowires (KNNWs) and further explored their use and effectiveness as optical probes at the nanoscale in our laser tweezer setup. We found that the nonlinear processes, including second-harmonic generation (SHG) and sum frequency generation (SFG), could be observed from the trapped KNNWs. Furthermore, we found that Fabry–Pérot type cavity enhanced SHG was realized by using a tunable NIR laser. The results suggest the possibility of synthetically tuning the lengths and diameters of nanowire cavities for increased harmonic conversion.

Related Media



(* – Denotes co-first authorship)
  1. Smith B*, Roder P*, et al. “Hot Brownian Thermometry and Cavity-Enhanced Harmonic Generation with Nonlinear Optical Nanowires.” Chemical Physics Letters. 639, 310-314, (2015).

Acquired Skills

Laser & Optical Setups

Integrating Multiple Lasers and Diodes
Custom Single Particle Spectroscopy Setups

Materials Characterization

Custom-Built MicroRaman
Single Particle Photoluminescence
Electron Diffraction Phase Analysis
Sum/Difference Harmonic Generation