Irradiation effects on Ge-H, Al-H, and other H-related point defects in cultured quartz crystals

Cultured quartz crystals with high concentration of Al and Ge have been investigated for their hydroxyl defects upon irradiation at 77 K before and after 300-K irradiation. The hydroxyl defects act as a source of hydrogen to-compensate the electron excess defects of aluminum centers during irradiation of quartz crystals. In this study, a comparison has been presented between differently grown Ge-doped crystals and a Sawyer Premium Q crystal. In particular, Ge-H, Al-H, and other H-related defect centers have been investigated and analyzed. During the irradiation process, some new bands appear at the expense of the already existing bands. A novel defect center absorbing at 3400 cm ^-1 has been noticed in two of the Ge-doped crystals. This band is a different species of point defects than the one absorbing at this frequency as one of the growth defect bands. A model has been assigned to this radiation-induced band. Other results have been discussed in terms of the fundamental considerations about the quartz crystal lattice