<i>In Situ</i>Diagnostics of the Crystalline Nature of Single Organic Nanocrystals by Nonlinear Microscopy

Abstract

We elucidate the crystalline nature and the three-dimensional orientation of isolated organic nanocrystals embedded in a sol-gel matrix, using a polarized nonlinear microscopy technique that combines two-photon fluorescence and second harmonic generation. This technique allows the distinction between monocrystalline structures and nanoscale polycrystalline aggregates responsible for incoherent second harmonic signals.