  Laser stimulated second and third harmonic generation effects in Fluorine
doped tin oxide (F:SnO2) nanostructures versus the fluorine content is
presented. The F:SnO2 nanostructures have been fabricated at various fluorine
doping concentrations by spray pyrolysis technique. The films exhibit
polycrystalline nature with a preferential growth orientation along (1 1 0)
diffraction plane as evident from x-ray diffraction studies. The optical
transmittance of the F:SnO2 films has increased from 68 percent to 80 percent.
Photoluminescence studies revealed that strong violet emission peak corresponds
to 400 nm and relatively weak red emission peak at about 675 nm was observed
for all the F:SnO2 films. Increase in the\b{eta}eff value upon fluorine
incorporation supports the applicability of the deposited films in passive
optical limiting applications. The principal origin of second harmonic
generation signals (SHG) for this type of nanostructures is played by the space
charge density acentricity due to the F doping. The enhanced second and third
harmonic generation signals observed on F:SnO2 nanostructures endorses the
credibility of these materials in various nonlinear optical trigger device
applications.
