Structural and luminescence studies of europium ions in lithium aluminium borophosphate glasses

Eu3+ doped borophosphate glasses with the chemical composition 20Li(2)O=30Al(2)O(3)=10B(2)O(3)=40P(2)O(5)=xEu(2)O(3) (where x=0.05 mol.%, 0.1 mol.%, 1.0 mol.%, 1.5 mol.% and 2.0 mol.%) were prepared by conventional melt quenching technique. The structural and luminescence properties of the prepared Eu3+ doped borophosphate glasses were studied and compared with reported results. The XRD pattern showed the amorphous nature of the prepared glasses. Whereas, the FTIR spectra revealed the vibrational modes in the prepared glasses. The bonding parameters ((beta) over bar and delta) were calculated through the excitation spectra. Judd-Ofelt (J-O) intensity parameters were calculated from the emission spectra and were used to determine transition probability (A), stimulated emission cross-section (sigma(E)(P)), radiative lifetime (tau(R)) and branching ratios (beta(exp)) for the transition D-5(0)-> F-7(j) (j=1, 2, 3 and 4) of Eu3+ ions. Furthermore, the luminescence intensity ratio (R) of D-5(0)-> F-7(2) to D-5(0)-> F-7(1) transition was also calculated. Transition D-5(0)-> F-7(2) had the highest value of stimulated emission cross-section and branching ratios and the results were comparable with the reported values. This indicated that the present glass is promising host material for Eu3+ doped fiber amplifiers.