The effect of intense x-ray beams on oxide glasses unveiled by means of photon correlation spectroscopy

In this thesis we aim to study the structural evolution under x-ray illumination in a selection of oxide glass formers as a function of the radiation dose. The irradiated specimens are investigated by means of XPCS experiments and also by means of “exsitu” experiments as luminescence, Raman and x-ray diffraction that have been carried out after the irradiation protocol. As far as we know, the “ex-situ” investigations here reported are the first in the field and have allowed us to evaluate the nature of the point defects, the structural modifications and the nature of the vibrational excitations of the samples exposed to the x-ray dose. The work carried out in the thesis has helped us to elucidate the microscopic evolution of the glass structure under irradiation and to verify whether the transformation can be envisioned as an evolution in the energy landscape, either as an “annealing” or as a “rejuvenation” process.