3RD-ORDER NONLINEAR-OPTICAL PROPERTIES OF SNO2 NANOPARTICLES

We have measured the third-order nonlinear susceptibilities chi((3)) o f SnO2 nanoparticles both naked and coated with a layer of stearic aci d by using Z-scan technique with 1.06 mu m pulse from a Q-switched Nd: YAG laser. The results show that the chi((3)) of these nanoparticles i s much larger than that of the bulk material. Moreover, we find that t wo-photon absorption is not present for the naked nanoparticles but it is present for the coated ones, and the chi((3)) of the latter is lar ger than that of the former. It is demonstrated that the surface situa tions of the nanoparticles have great influence on their nonlinear opt ical properties.