Impact of Bi2O3 on structural properties and lasing effects in Nd3+ doped bismuth phosphate glasses at 1.053μm emission

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2017-06, Vol.181, p.264-269
• Main Authors: Damodaraiah, S., Reddy Prasad, V., Ratnakaram, Y.C.
• Format: Article
• Language: English
• Subjects: 31P MAS NMR spectra; Bismuth phosphate glass; Emission cross-section; FT-IR spectra; Judd-Ofelt parameter; Photoluminescence
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2017.03.060

Influence of addition of bismuth oxide (Bi2O3) on structural and optical properties of 0.5Nd3+doped different phosphate glasses prepared by melt quenching technique were reported. The structural properties were analysed by FT-IR and 31P MAS NMR techniques. 31P NMR results showed that, with the variation of Bi2O3 concentration in the prepared phosphate glass matrices there was no significant change in the structure. The optical properties have been analysed using Judd–Ofelt (J-O) theory. From absorption spectra, three phenomenological J–O intensity parameters (Ω2, Ω4, Ω6) have been calculated and these parameters were used to estimate the radiative properties. The J-O intensity parameters increased with increase in the concentration of Bi2O3, which confirmed the higher covalency, asymmetry and rigidity. The branching ratios (β) and emission cross-sections (σ) were calculated from the emission spectra of Nd3+ doped bismuth phosphate (BiP) glasses. Among different glass matrices 15mol% of Bi2O3 glass matrix has higher β and σ values which are useful for the laser applications. The improved emission cross-section value with the addition of Bi2O3 content results low threshold and high gain applications. The decay curves of all these BiP glasses showed single exponential behaviour. [Display omitted] •Solid state NMR spectra confirmed Q2 tetrahedra structure for all bismuth phosphate (BiP) glass matrices.•Judd-Ofelt parameter, Ω2 is higher for Bi-15 glass which confirm strong covalency between Nd3+ ions and ligand anions.•High σe is observed for 4F3/2→4I11/2 transition of Nd3+ ions in Bi-15 glass matrix indicating the effective laser emission.•Decay curves of 4F3/2 state exhibits single exponential nature for all Nd3+ doped glass matrices.