Effect of irradiation on photoluminescence and optical absorption spectra of Li2B4O7:Mn and Li2B4O7:Ag single crystals

Effects induced by high-dose irradiation on manganese- and silver-doped Li2B4O7 (lithium tetraborate, LTB) single crystals were monitored by photoluminescence and optical absorption spectroscopy. High-dose (1.0×103 and 1.2×104 Gy) irradiation of the samples was performed using high-energy, short-time (4 MeV, 2.6 μs) electron pulses of a linear electron accelerator. Changes in the oxidation states of dopants were revealed. Recharging of manganese Mn2+→Mn3+ and Ag+→Ag0 were observed. Ionization process Mn2+→Mn3++e− and creation of Ag0-nanoparticles are supposed.