Spontaneous oxygen loading into SiO2 glass by thermal anneal

The interstitial oxygen molecules (O2) in SiO2 glass were detected down to ∼1015 cm−3 by photoluminescence of O2 at 1272 nm excited at 765 nm by a continuous-wave titanium sapphire laser. It was evidenced that SiO2 glass thermally annealed in air between 800 and 1100 °C spontaneously absorbs ∼1016 cm−3 of O2 from the ambient atmosphere. The time-dependent concentration change of the interstitial O2 allows the determination of both the diffusion coefficient and the solubility of the interstitial O2.