Reverse saturable absorption in nano colloidal Ge28Sb12Se60 chalcogenide glass

We report the preparation and investigation of nano colloidal solutions of Ge28Sb12Se60 chalcogenide glass based on nonlinear optical transmission by the open-aperture Z-scan technique, using nanosecond laser pulses, at the excitation wavelengths of 532 nm. The Z scan spectra reveal a strong non linear absorption (reverse saturable absorption) for the nano colloid Ge28Se60Sb12 solutions. Observation of optical limiting at excitation wavelength suggests the potential of these materials to be used as optical limiters.