Comparative study of spectroscopic properties of Er3+-ion doped K2O/KF-Gd2O3-P2O5 glass systems

The two phosphate glasses with composition 17K2O−17Gd2O3−65P2O5−01Er2O3 and 17KF−17Gd2O3−65P2O5−01Er2O3 composition were synthesized by conventional-melt quenching techniques to study comparatively the spectroscopic, Judd–Ofelt (JO), radiative properties and NIR-luminescent properties. The Urbach energy of K2O−Er and KF-Er samples was 0.3547 and 0.4799 eV. The observed trend is Ω2>Ω4>Ω6 and Ω2>Ω6>Ω4 for JO-intensity-parameters for K2O−Er and KF-Er glasses. Moreover, K2O−Er has higher Ω4 and Ω6 values, thus having more rigidity and viscosity than KF-Er. The measured values of full-width-half-maximum (FWHM) for K2O−Er and KF-Er glasses 54.60 and 58.27, respectively. The measured values of FWHM for K2O−Er and KF-Er glasses were 54.60 and 58.27, respectively. The 𝐴ð'... values are 417.61 and 3038 for K2O−Er and KF-Er glasses, respectively. The radiative lifetime (ðoeð'...) for K2O−Er and KF-Er glasses is 2.39 ms and 3.18 ms, respectively. Utilizing McCumber theory the 𝐺(ðoe†,ð>½) is positive and population-inversion is more than 0.4 for both glasses. Both samples have flat gain-bandwidth in the range of 1505–1585 nm, which covers the S-, C-, and L-bands of the low-loss optical communication-window. It is evident from all these results that the prepared glass samples have the potential for a low-threshold and high gain NIR laser and optical-fiber amplifier.