Cathodoluminescence versus dynamical epitaxy of Ba-ion irradiated α-quartz

Doping α-quartz with photoactive ions without destroying its crystalline structure appears to be a promising way to tune its luminescent and structural properties. We have achieved dynamic solid phase epitaxial regrowth and cathodoluminescence of 175keV Ba-ion irradiated α-quartz in the temperature range from 300 to 1170K. Rutherford Backscattering Channeling analysis showed that the amorphous layer produced by 1×1015 Baions∕cm2 at 300K had almost disappeared at an implantation temperature of 1123K. Room temperature cathodoluminescence exhibited dramatic changes in the optical spectra as a function of the implantation temperature and allowed to distinguish between color centers related to quartz, ion-irradiated silica and implanted Ba. Between 770 and 1100K, room-temperature cathodoluminescence showed a predominant blue and other weak bands connected to various known defects in the Si-O-Si network. However, after achieving almost complete solid phase epitaxial recovery, only a violet band at 3.4eV remained, which we attribute to Ba-related luminescence centers.