Figure 7
From: Narrow Energy Gap between Triplet and Singlet Excited States of Sn2+ in Borate Glass
Plausible energy scheme for photoluminescence process of Sn2+ emission centre.
(a) (Sn0.02Sr0.98)B6O10 crystal21, (b) Sn2+-doped silica glass23 and (c) 0.5SnO-24.5SrO-75B2O3 glass. Solid lines and dashed lines indicate radiative and nonradiative transitions, respectively. Photon energies of each excitation (blue) and relaxation (red) processes are shown.
