Correlating Second Harmonic Optical Responses of Single Ag Nanoparticles with Morphology

摘要

The linear and nonlinear optical properties of nanoparticles are of significant importance for fundamental science and technological applications. The second harmonic (SH) response of nanoparticles is particularly interesting due to the potential dependence on particle shape and deviations from high symmetry (e.g., spherical). However, ensemble measurements (e.g. SH from colloidal solutions) obscure deeper insights due to the inevitable inhomogeneity of particle shape and size. Thus, measurements on a single-particle level are necessary to gain a more complete understanding of the optical properties of nanocrystal materials. Undertaking such measurements is, however, impeded by the lack of a methodology allowing precise correlation of optical measurements and high-resolution imaging of the particle morphology by transmission electron microscopy (TEM).