title: Laser-diode-excited intense luminescence and green-upconversion in erbium-doped bismuth-germanate-lead glasses.
abstract: We investigate the spectroscopic properties of the 1.5-microm emission from the (4)I(13/2)-->(4)I(15/2) transition of Er(3+) ions in bismuth-germanate-lead glasses for applications in broadband fiber amplifiers. The emission peak locates at 1532nm with a full width at half-maximum (FWHM) of approximately 65nm. The measured lifetime and the calculated emission cross-section of this transition are 3.3ms and 8.66x10(-21)cm(2), respectively. IR-to-green-upconversion occurs simultaneously upon excitation of the 1.5-microm emission with a commercially available 980nm laser diode. Effects of PbF(2) content on the thermal stability, structure and spectroscopic properties of Er(3+)-doped bismuth-germanate-lead glasses have been examined. We find that the substitution with PbF(2) provides a couple of potentials: shortening the UV cutoff band and decreasing the phonon energy of host glasses. Codoping of Yb(3+) significantly enhances both the green-upconversion and 1.5-microm emission intensity by means of a nonradiative Yb(3+)-->Er(3+) energy transfer. Energy transfer processes and nonradiative phonon-assisted decays could account for the population of the (2)H(11/2) level, which is an emitting level of the green-upconversion of Er(3+). The results indicate the possibility towards the development of bismuth-germanate-lead based glasses as photonics devices.
authors: Institute of Optical Communication Materials, South China University of Technology, Guangzhou 510641, People's Republic of China.
authors: G F
authors: GF
authors: Yang
authors: Q Y
authors: QY
authors: Zhang
authors: T
authors: T
authors: Li
authors: D M
authors: DM
authors: Shi
authors: Z H
authors: ZH
authors: Jiang
mesh_terms: D001729:Bismuth / Q000737:chemistry*; D004553:Electric Conductivity; D004871:Erbium / Q000737:chemistry*; D005857:Germanium / Q000737:chemistry*; D005898:Glass / Q000737:chemistry*; D054023:Lasers, Semiconductor; D007854:Lead / Q000737:chemistry*; D049449:Luminescence; D013050:Spectrometry, Fluorescence; D013059:Spectrum Analysis, Raman; D013696:Temperature; D013816:Thermodynamics; D013997:Time Factors
chemical_list: D005857:Germanium; C042364:bismuth germanium oxide; D007854:Lead; D004871:Erbium; D001729:Bismuth