Investigation of nonlinear properties of CdS-doped glasses

The dynamics of photodarkening and transient absorption in commercial CdS-doped filter glass Asahi Y45 has been investigated at room temperature using pump and probe spectroscopy. The fresh spot of the sample was irradiated by pump pulse with the wavelength of 355 nm above the band gap and the probing was done at different wavelengths (1064, 760, and 469 nm). Influence of exposure as well as probe wavelength on dynamics of carriers has been investigated. The long lived photoinduced absorption dynamics corresponding to the higher probe photon energy illustrates the dominant contribution of the trapping states from the glass matrix. A simple model has been presented to understand the photoinduced carrier dynamics. The amplitude of differential absorbance as well as the photodarkening dynamics connected to the interior states are found to be in good agreement with the Drudeʹs free electron model.