UV and VUV optical excitations in wide band gap materials doped with rare earth ions: 4f-5d transitions

From the point of view of luminescence applications, large band gap materials such as fluoride compounds are suitable matrices into which a small concentration of foreign ions called activators can be incorporated. To improve the knowledge of the optical properties of the overall system, the investigation of the different interactions of UV and WV electromagnetic radiations with the condensed matter was undertaken. The excitation of the luminescence induced in rare earth ion activators doped in LiYF4, LaF3 and YF3 was recorded in a wide continuous spectral region from 5 to 15 eV using synchrotron radiation as a photon source. The main interest of this work was focused on the localization in energy of the different photon absorption mechanisms occurring in these fluoride compounds doped with rare earth ions.