A study of spectroscopic, optical and physical properties of novel fluorophosphate glass materials doped with rare earth ions

Two sets of Nd2+, Er3+ and Yb3+ doped alkaline-free MgF2-BaF2-Ba(PO3) 2-Al(PO3)3 (MBBA system) and Bi(PO3) 3-Sr(PO3)2-BaF2-MgF 2 (BSBM system) are successfully prepared with the aim of using them as active media. In order to evaluate the potential for the use of laser media, several parameters in physical, optical, and spectroscopic properties should be carefully investigated.; For the MBBA system, basic physical and optical properties are carried out. The effects of thermo-mechanical, and mechanical properties on various R.E. doped glasses are reported as a function of types of dopants and their concentration. The density of the current system with R.E. dopants increases because of cationic field strength (CFS) effect. Knoop hardness decreases with the loading time and R.E. concentration because of indentation size effect (ISE) effect.; For spectroscopic analysis for Er3+, intensity parameters (Ot) are calculated from least square fitting between measured and calculated oscillator strength. Spontaneous emission probability ( Arad), branching ratio (beta) and predicted radiative lifetime (taurad) have been obtained for certain excited states of the Er3+. Emission cross section for the 4I 13/2 → 4I15/2 transition was determined by Fuchtbauer-Ladenburg method for the MBBA and BSBM system, respectively.; For spectroscopic analysis for Nd3+, Judd-Ofelt analysis is performed for the MBBA and BBBM system doped with Nd2O 3 to evaluate the spontaneous emission probability as well as quality factor and branching ratio. The variation of intensity parameters O 2, O4, and O 6 are analyzed as a function of Nd2O3 concentration.; Spectroscopic properties including emission cross section and lifetime are reported as a function of Yb2O3 concentration for MBBA and BBBM system. To our knowledge, the emission cross-section sigma emi, which was found to be ∼0.87, and 1.37 pm2 at the lasing wavelength of 996 nm for the MBBA and BBBM system, is the highest one among fluorophosphate glasses, respectively. The combination of outstanding spectroscopic (high emission cross section and gain coefficient) and optical (low dispersion and small nonlinear refractive index) properties demonstrates that the current Yb3+ activated fluorophosphate glass is an excellent candidate material for fiber and waveguide lasers.