Optical absorption spectra of gold nano-clusters in potassium borosilicate glass

Optical absorption spectra for gold particles grown in two different potassium borosilicate glasses at 600 °C were measured. In the more viscous glass, only extremely small particles formed by nucleation of gold atoms in the glass. In the less viscous glass, the particles nucleated and grew to larger sizes, forming a plasmon absorption band. Particles sizes were calculated from the optical absorption spectra, and the diffusion coefficient of gold in the glass was also calculated. A transmission electron micrograph (TEM) showed a distribution of particle sizes resulting from both nucleation and growth of the particles. The influence of this size distribution on kinetics of growth and the optical absorption spectra was discussed.