Double-peak structure in optical absorption spectrum of Ag-BaO composite thin film

The optical absorption properties of Ag-BaO composite thin film were measured, and two absorption peaks were observed in the visible and near-infrared bands. The dominant absorption peak in the visible region is considered to result from surface plasmon resonance of Ag nanoparticles embedded into the matrix. The other absorption peak is attributed to the transition of bound electrons at the impurity energy level of the BaO semiconductor matrix, and the presence of such an impurity energy level is related to the negative ion vacancies caused by the excess barium in the BaO crystal.EI06423-425+4302