title: Absorption and emission characteristics of Er3+ ions in alkali chloroborophosphate glasses.
abstract: Alkali chloroborophosphate glasses containing 1 mol% of Er3+ ions were studied experimentally using the absorption and emission spectroscopy. The energy level scheme for the 4f11 (Er3+) electronic configuration was deduced from the observed band energies of the absorption spectra in terms of a parametrized Hamiltonian using the various free-ion spectroscopic parameters. Oscillator strengths (f) measured from the absorption spectra have been analyzed using the Judd-Ofelt theory to evaluate the three intensity parameters omegalambda (lambda = 2, 4 and 6). Reasonable agreement between the measured and calculated f values has been found. Electric and magnetic dipole transition probabilities, fluorescence branching ratios, integrated emission cross sections and radiative lifetimes were calculated for all the excited states of Er3+ ions. The non-radiative (WNR) relaxation rates from the excited levels to the next lower levels have been calculated and the relationship between the energy gap and non-radiative relaxation rate has been established. These results were used to predict the possible potential laser transitions in Er-doped alkali chloroborophosphate glasses.
authors.affiliation: Department of Physics, Sri Venkateswara University, Tirupati, India. lrmoorthy@usa.net
authors.forename: L R
authors.initials: LR
authors.lastname: Moorthy
authors.forename: T S
authors.initials: TS
authors.lastname: Rao
authors.forename: K
authors.initials: K
authors.lastname: Janardhnam
authors.forename: A
authors.initials: A
authors.lastname: Radhapathy
mesh_terms: D004871:Erbium / Q000737:chemistry*; D005898:Glass / Q000737:chemistry*; D008956:Models, Chemical; D013054:Spectrophotometry, Atomic / Q000379:methods*
chemical_list: D004871:Erbium