LiIO 3 nanocrystals in SiO 2 xerogels, a new material for nonlinear optics

In recent years, a large amount of activity has been carried out searching new materials for second order non-linear optics. Nanostructured materials composed of a host matrix and optical active nanocrystals form a new part of this research field. Our present work consists in "doping" SiO 2 matrices with 5 to 30% mass of LiIO 3 nanocrystals. Indeed, α-LiIO 3 is a compound known to be very efficient for second harmonic generation (SHG). This nanocomposite glass has been developped using sol-gel technics. Bulk samples have been first studied showing nanocrystallites with size ranging from 50 nm to 400 nm and second harmonic generation (SHG). Then thin layers have been elaborated using dip coating and spin coating technics. Being given that LiIO 3 crystals present structurally a strong dipolar moment, non-linear optical properties could be enhanced using Corona discharges to orientate nanocrystals. This paper relates the fabrication process and the structural and optical characterizations of bulk and thin layer material.