title: Structural and luminescence behavior of Er(3+) ions doped Barium tellurofluoroborate glasses.
abstract: Er(3+) doped Barium tellurofluoroborate glasses (BTFBxE) with the chemical composition (30-x)TeO2+30B2O3+20BaO+20BaF+xEr2O3 (where x=0.01, 0.05, 0.1, 0.5, 1.0 and 2.0 in wt%) were prepared following the melt quenching technique. The different vibrational modes of borates and tellurites in the prepared glasses were explored through FTIR and Raman spectra. The optical absorption spectra have been used to determine the ionic/covalent nature of the metal-ligand bond in the prepared glasses with the help of Nephelauxetic ratio (β) and bonding parameter (δ) studies. The optical band gap of direct and indirect allowed transitions were determined from Tauc's plot and the variations of band gap energy with structural arrangements were discussed. The Urbach energy values were determined and the relatively lower values of the Urbach's energy reveal the minimal degree of disorderness in the prepared glasses. The oscillator strengths (fexp and fcal) and Judd-Ofelt (JO) intensity parameters (Ω2, Ω4 and Ω6) were calculated with the application of JO theory and the trends of the JO intensity parameters are found to be Ω2>Ω6>Ω4 for all the prepared glasses with a minimum variation in Ω2 intensity parameter values. A bright green emission was observed from the (2)H11/2+(4)S3/2→ (4)I15/2 transition and the radiative properties such as transition probability (A), stimulated emission cross-section (σP(E)), branching ratio (βr) and radiative lifetime (τ) were calculated using the JO parameters. The suitability of the prepared glasses for the fabrication of photonic devices were also discussed and reported in the present work.
authors.affiliation: Department of Physics, Gandhigram Rural University, Gandhigram 624 302, India.
authors.forename: K
authors.initials: K
authors.lastname: Annapoorani
authors.affiliation: Department of Physics, K.S.Rangasamy, College of Technology, Trichengode 637 215, India.
authors.forename: K
authors.initials: K
authors.lastname: Maheshvaran
authors.affiliation: Department of Physics, Gandhigram Rural University, Gandhigram 624 302, India.
authors.forename: S
authors.initials: S
authors.lastname: Arunkumar
authors.affiliation: Radiological Safety Division, IGCAR, Kalpakkam 603 102, India.
authors.forename: N
authors.initials: N
authors.lastname: Suriya Murthy
authors.affiliation: Department of Physics, Gandhigram Rural University, Gandhigram 624 302, India. Electronic address: mari_ram2000@yahoo.com.
authors.forename: K
authors.initials: K
authors.lastname: Marimuthu
mesh_terms: D001464:Barium / Q000737:chemistry*; D001881:Borates / Q000737:chemistry*; D004871:Erbium / Q000737:chemistry*; D005898:Glass; D049449:Luminescence; D055620:Optical Phenomena; D017550:Spectroscopy, Fourier Transform Infrared; D019265:Spectroscopy, Near-Infrared; D013059:Spectrum Analysis, Raman; D013816:Thermodynamics; D014961:X-Ray Diffraction
chemical_list: D001881:Borates; D001464:Barium; D004871:Erbium
keywords: Band gap; Judd–Ofelt parameter; Nephelauxetic ratio; Optical properties; Urbach energy