Synthesis and characterization of plasmonic hybrid nanostructures for enhanced second harmonic generation

Second harmonic generation at the nanoscale presents intriguing opportunities in numerous fields, including bioimaging, medical therapies and diagnostics, and chemical sensing. The practical application of second harmonic nanomaterials is, however, limited by the inherently weak nature of second harmonic responses, particularly at increasingly small scales. As such, there is a need to boost the weak second harmonic responses of nanomaterials. The proposed method of enhancing second harmonic generation at the nanoscale, which will be discussed in this thesis, is to decorate porous LiNbO3 particles with small silver nanoparticles. Herein, ∼8-13 nm silver nanoparticles were grown directly onto ∼400 nm LiNbO3 particles via a photocatalytic method. The resulting hybrid Ag–LiNbO3 exhibited a maximum ∼28-fold increase in second harmonic efficiency relative to bare LiNbO3 particles.