Influence of gamma irradiation on photoluminescence and nonlinear optical properties of Eu³⁺ activated heavy metal borate glasses

Gamma irradiation effect on absorption, photoluminescence (PL), and nonlinear optical (NLO) features of Eu³⁺ doped heavy metal borate glasses was studied and elucidated in detail. With blue light excitation, the emission intensity of Eu³⁺ doped glass was monitored with respect to irradiated dose. The PL intensity of the glasses was reduced with a raise in gamma dose rate because of the formation of colour centres. The quality of the emission colour of the pre- and post-irradiated glasses was analysed using 1931 CIE system. The Nonlinear Optical (NLO) features were examined by the Z–scan technique in the near–infrared spectral region and using femtosecond pulse excitation. The NLO attributes were enhanced with increase gamma irradiation dose. These enhancements are ascribed to the development of defects and non–bridging oxygens when irradiated with gamma radiation. The enhancement of NLO coefficients with gamma irradiation dose suggest the high dose irradiated glasses are useful for photonic device applications, particularly for optical limiters.