Frequency doubling by nonlinearity of TiO₂ nanomaterial

We reported titanium dioxide nanoparticles solution (TiO₂ NPS) preparation by the sol-gel method. The produced NPS was employed as a liquid crystal to generate the second harmonic (SH) of one part of the pumping Nd: YAG laser at different pumping intensities. The remaining part of the pumping laser was focused on a stander nonlinear material (NPP63) to produce another SH pulse (to be used as a reference). Then the two SH pulses (one from TiO₂ and one from NPP63) were used to calculate the nonlinear coefficient (β) of the synthesized TiO₂ Nano solution. The suggested method represents a simple and inexpensive setup for calculation β by excluding the very expensive femtosecond laser used in previous studies. The results reveal that β for the prepared TiO₂ nanoparticles is very large (5.3×10^-26 esu).