In the last decades first-principles studies have provided a remarkable improvement of our understanding of point defects in solids, in particular of those responsible for the radiation induced attenuation of optical fibers [1]. Synthetic vitreous silica is currently the preferred material for the production of optical fibers. Since doping of silica with various materials, e.g. phosphorus and aluminium, is routinely employed for specific purposes, the study of the induced point defects in the fiber may in general require the understanding not only of silica, but also of the doping material and its native defects. In this talk, by means of first-principles techniques, I discuss, on one hand, structural models of point defects capable to explain experimental (e.g. electron paramagnetic, optical absorption, Raman) results in P-doped silica and in phosphate glasses [2,3], on the other hand, I provide a short overview of the modelling of some amorphous oxides structures employed in our point defects investigations [4].
[1] S. Girard et al. Rev. Phys. 4, 10032 (2019).
[2] L. Giacomazzi et al. J. Phys. Chem. C 125 , 8741 (2021).
[3] L. Giacomazzi et al. Sci. Rep. 9, 7126 (2019).
[4] N. S. Shcheblanov et al, Phys. Rev. B 100, 134309 (2019).
Paolo Umari
