title: Optical spectroscopy of lanthanide ions in ZnO-TeO2 glasses.
abstract: Zinc tellurite glasses of compositions 19ZnO-80TeO2-1Ln2O3 with Ln = Eu, Er, Nd and Tm were prepared by melt quenching. The absorption spectra were measured and from the experimental oscillator strengths of the f-->f transitions the Judd-Ofelt parameters ohm(lambda) were obtained. The values of the ohm(lambda) parameters are in the range usually observed for oxide glasses. For Nd3+ and Er3+, luminescence spectra in the near infrared were measured and the stimulated emission cross sections sigma(p) were evaluated for some laser transitions. The high values of sigma(p), especially for Nd3+, make them possible candidates for optical applications. Fluorescence line narrowing (FLN) spectra of the Eu3+ doped glass were measured at 20 K, and the energies of the Stark components of the 7F1 and 7F2 states were obtained. A crystal field analysis was carried out assuming a C2v site symmetry. The behaviour of the crystal field ratios B22/B20 and B44/B40 agrees reasonably well with the values calculated using the geometric model proposed by Brecher and Riseberg. The crystal field strength at the Eu3+ sites appears to be very low compared to other oxide glasses.
authors.affiliation: Istituto Nazionale per la Fisica della Materia and Dipartimento di Fisica, Università di Trento, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Rolli
authors.forename: K
authors.initials: K
authors.lastname: Wachtler
authors.forename: M
authors.initials: M
authors.lastname: Wachtler
authors.forename: M
authors.initials: M
authors.lastname: Bettinelli
authors.forename: A
authors.initials: A
authors.lastname: Speghini
authors.forename: D
authors.initials: D
authors.lastname: Ajò
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D003461:Crystallography; D005898:Glass / Q000737:chemistry*; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D013053:Spectrophotometry / Q000379:methods*; D013691:Tellurium / Q000737:chemistry*; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D028581:Lanthanoid Series Elements; C026660:tellurous acid; D013691:Tellurium; D015034:Zinc Oxide