Role of Gd${}_2$O${}_3$ on tuning structural and optical properties of low phonon energy MgF${}_2$ borate glass

The glass of composition 75B${}_2$O${}_3$-5Al${}_2$O${}_3$-15MgF${}_2$-(5-x)Li${}_2$O-xGd${}_2$O${}_3$ (with x = 0, 0.2, 0.4, 0.6) mole% was prepared using the fast melt-quenching technique, so as to investigate the manipulation of gadolinium oxide on the structure and spectroscopic properties of these compositions to be applicable in optoelectronic applications, which were investigated by different techniques. From vibrational investigation, it was revealed that the Gd${}_2$O${}_3$ influence on glass structure increased the non-bridging oxygen at the expense of BO${}_3$ groups. From spectroscopic investigation, as the incorporation of the Gd${}_2$O${}_3$ component increases in the oxyflouro structure, the energy band-gap property decreases, indicating an increase in the proportion of localized states formed near the conduction band for electrons. The band gap can be reduced as a result of the interaction between localized states and the conduction band. Moreover, ε${}^{\prime }$ and ε${}^{\prime \prime }$ rise with increased Gd${}_2$O${}_3$ content in the glass matrix and photon energy due to polarization. In addition to refractive index and optical conductivity, changing the phonon energy to a certain extent revealed that the prepared glass can be considered a fiber amplifier.