title: Optical absorption and photoluminescence properties of Nd3+ doped mixed alkali phosphate glasses-spectroscopic investigations.
abstract: Spectroscopic investigations were performed on 68NH(4)H(2)PO(4).xLi(2)CO(3)(30-x)K(2)CO(3) and 68NH(4)H(2)PO(4).xNa(2)CO(3)(30-x)K(2)CO(3) (where x=5, 10, 15, 20 and 25) glasses containing 2 mol% Nd(2)O(3). Various spectroscopic parameters (Racah (E(1), E(2), E(3)), spin-orbit (xi(4f)) and configuration interaction (alpha)) are reported. Judd-Ofelt intensity parameters (Omega(2), Omega(4), Omega(6)) are calculated for Nd(3+) doped two mixed alkali phosphate glass matrices. From the magnitude of Judd-Ofelt parameters, covalency is studied as a function of x in the glass matrix. Using Judd-Ofelt intensity parameters, total radiative transition probabilities (A(T)), radiative lifetimes (tau(R)), branching ratios (beta) and integrated absorption cross sections (Sigma) have been computed for certain excited states of Nd(3+) in these mixed alkali phosphate glasses. Emission cross sections (sigma(P)) are calculated for the two transitions, (4)G(7/2)-->(4)I(11/2) and (4)G(7/2)-->(4)I(13/2) of Nd(3+) in these mixed alkali phosphate glasses. Optical band gaps (E(opt)) for direct and indirect transitions are reported.
authors.affiliation: Department of Physics, S.V. University Post-Graduate Centre, Kavali 524 201, India. ratnakaram_yc@yahoo.co.in
authors.forename: Y C
authors.initials: YC
authors.lastname: Ratnakaram
authors.forename: N V
authors.initials: NV
authors.lastname: Srihari
authors.forename: A Vijaya
authors.initials: AV
authors.lastname: Kumar
authors.forename: D Thirupathi
authors.initials: DT
authors.lastname: Naidu
authors.forename: R P S
authors.initials: RP
authors.lastname: Chakradhar
mesh_terms: D000042:Absorption; D000468:Alkalies / Q000737:chemistry*; D005453:Fluorescence; D005898:Glass / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry; D049449:Luminescence; D009354:Neodymium / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D011188:Potassium / Q000737:chemistry; D013057:Spectrum Analysis
chemical_list: D000468:Alkalies; D010710:Phosphates; D009354:Neodymium; D008094:Lithium; D011188:Potassium