Second harmonic generation imaging with a kHz amplifier [Invited]

Nonlinear optical imaging is a powerful method for observing bulk and interfacial phenomena in time and space. Here, we present a step-by-step description of how to carry out second harmonic generation imaging with a kHz amplifier laser system and demonstrate its applicability for SHG microscopy studies of highly size-resolved colloidal CdSe quantum dots having radii of 1-2 nm deposited on glass slides. It is found that not all quantum dots are SHG active, which suggests that environmental effects and particle distributions are important for SHG activity of quantum dots. (C) 2011 Optical Society of America