Surface dissolution and diffusion of oxygen molecules in SiO2 glass

Surface dissolution and diffusion of oxygen molecules (O 2 ) in SiO 2 glass were studied by their photoluminescence at 1272 nm excited with a titanium sapphire laser oscillating at 765 nm. The dissolution of O 2 from ambient atmosphere at both surfaces was much faster than the following diffusion of O 2 into SiO 2 glass, indicating that the surface dissolution is not the rate-limiting step for the saturation of SiO 2 glass with O 2 . The time- and temperature-dependent concentration changes of O 2 allow to evaluate the diffusion coefficient and the saturation solubility of O 2 in SiO 2 glass.