Judd-Ofelt parametrization and radiative analysis of Dy3+ ions doped Sodium Bismuth Strontium Phosphate glasses

Abstract

This paper focus on spectroscopic analysis of Sodium Bismuth Strontium Phosphate (NaBiSrP) glasses doped with dysprosium (Dy3+) ions using X-ray Diffraction (XRD), Raman Spectroscopy, Fourier Transform-Infrared (FT-IR) Spectroscopy, Photoluminescence (PL) Spectroscopy and decay spectral measurements. Excitation spectra of the glasses under 575 nm emission possess a sharp band corresponding to 6H15/2 → 6P7/2 transition (350 nm). Subsequently, emission spectra recorded under 350 nm excitation exhibit sharp bands at 480 and 575 nm. The Judd-Ofelt (J-O) theory has been applied to the measured energies of the absorption bands/oscillator strengths to study various radiative parameters such as radiative and total transition probabilities (AR &AT), branching ratios (βR) and radiative lifetimes (τR) for the prominent fluorescent levels of Dy3+ doped NaBiSrP glasses. It was observed that glass D has got highest value of Ω2 signalling high symmetry of crystal field of Dy3+ ions and a maximum intensity for hypersensitive transition. PL decay analysis reveal experimental lifetimes of 4F9/2 energy level under 350 nm excitation decreases with increase in Dy3+ ion concentration indicating the energy transfer between Dy3+ ions. The Inokuti-Hirayama (I–H) curve fitting was also done for the glass with the highest Dy3+ ion concentration showing dipole-dipole interaction. From the above-mentioned results, it is apt to say that the as synthesized phosphate glasses doped with Dy3+ ions are quite suitable for designing the white light emitting diodes (wLEDs) and other optoelectronic devices.