Nonlinear optical studies on nanocolloidal Ga-Sb-Ge-Se chalcogenide glass

In this paper we report the preparation and the optical studies on nanocolloidal solutions of Ga5Sb10Ge25Se60 for the first time. The optical band gap of the material is found to be tunable depending on the cluster size. The cluster formation and the dependence of the cluster size with concentration were confirmed by the scanning electron microscope analysis. Nonlinear optical characterization of these solutions were studied by the Z-scan technique using an Nd:YAG laser (532 nm, 7 ns, 10 Hz). The studies show that the material is highly nonlinear. The solutions show reverse saturable absorption, which makes it useful for optical limiting applications. (C) 2010 American Institute of Physics. [doi:10.1063/1.3481097]