Ultraviolet-radiation-induced chemical reactions through one-and two-photon absorption processes in GeO 2 –SiO 2 glasses

摘要: Photochemical reactions in 10 GeO(2)-90 SiO(2) glass induced by irradiation with excimer lasers (KrF, 5.0 eV, XeCl, 4.0 eV) and a Hg lamp (4.9 were examined. The generated two types of paramagnetic defect, an electron-trapped center associated fourfold coordinated Ge ions self-trapped hole on bridging oxygen. Taking the optical band gap (~7.1 obtained this work power density laser pulses [10-90 mJ/(cm(2) pulse), pulse duration 20 ns] into account, we concluded that these centers formed band-to-band excitation two-photon absorption process. On other hand, illumination ( 16 mW/cm(2)) caused formation E' from preexisting oxygen-vacancy-type defects one-photon These kinds reaction proceed independently, depending densities UV beams, at least our experimental condition.