Abstract

We have developed a luminescent marker using the second harmonic generation (SHG) from noncentrosymmetric BaTiO₃ nanocrystals. These nanoparticles are attractive due to their stable, non-saturating and coherent signal with a femtosecond-scale response time and broad flexibility in the choice of excitation wavelength. In this paper, we report the SHG response of BaTiO₃ nanocrystals under a circularly polarized excitation. We observed a more uniform SHG signal intensity from nanocrystals of different crystal orientations under a circularly polarized excitation. The three-dimensional (3D) SHG fields generated from the SHRIMPs were recorded by a harmonic holographic microscope. Sub-micron resolution in both lateral and axial directions has been achieved. We show that the circularly polarized excitation is useful for harmonic holographic microscopy.

© 2009 OSA/SPIE