Abstract

In this paper, we report experimental observations of second harmonic generation (SHG) from single micron-sized polystyrene (PS) spheres on a substrate. The observations are unusual because the signal magnitude can be enormously enhanced compared to the substrate response. This enhancement depends on particle size and sphere composition. Micronsized spheres such as these are important in a variety of fields ranging from colloidal science, to optical tweezing and microrheology in cell biology. The nonlinear optical and lasing properties of such particles have also been of interest over the years,¹-⁴ but little work has been done on second-order nonlinear optical properties of isolated particles.

© 1999 Optical Society of America