Effect of neodymium ions on the photosensitivity of photo-thermo-refractive glass.

Neodymium doping of photo-thermo-refractive (PTR) glass leads to a fast non-radiative depopulation of excited states of cerium ions, which are responsible for the glass photosensitivity. The non-radiative energy transfer from cerium to neodymium ions results in a decrease in the efficiency of photoelectron generation under UV irradiation. Emission spectra and fluorescence decay curves of cerium ions under UV excitation were investigated. Absorption spectra of the glasses were obtained as well to distinguish the reabsorption processes and the non-radiative energy transfer mechanisms. It was found that as Nd 2 O 3 concentration increases from 0 to 2 mol%, cerium ions average lifetime decreases from 44.5 to 28 ns, while the energy transfer efficiency reaches 37 %. It was also found that Förster resonance energy transfer may compete with other relaxation mechanisms and the Förster distance for the Ce3+-Nd3+ pair in PTR glass is ∼0.33 nm. This study has important implications for future research; it informs future studies on optimizing the photosensitivity of the PTR glass and choosing rare-earth activators. • Doping of photo-thermo-refractive glass with Nd3+ ions reduces the glass photosensitivity. • Non-radiative ET from Ce to Nd leads to fast depopulation of Ce and decreases the efficiency of photoelectron generation. • Energy transfer efficiency increases from 5 to 37 % when increasing neodymium concentration from 0.25 to 2 mol%. [ABSTRACT FROM AUTHOR]