title: [Multiply upconversion emission in oxyfluoride ceramics].
abstract: Oxyfluoride ceramics with the host composition of SiO2 and PbF2 have been prepared. X-ray diffraction analysis of the ceramics revealed that fluoride type beta-PbF2 solid solution regions are precipitated in the glass matrix. Rare earth ions in the beta-PbF2 solid solution show highly efficient upconversion performance due to the very small multi-phonon relaxation rates. Eight upconversion emission bands whose central wavelength are 846, 803, 665, 549, 523, 487, 456 and 411 nm have been observed when the sample was excited with 930 nm diode light. Four possible energy transfer processes between Er3+ and Yb3+ cause the electronic population of high energy level of Er3+ and realize the abound upconversion luminescence bands.
authors.affiliation: Physics Department, Xiangtan University, Xiangtan 411105, China.
authors.forename: Si-guo
authors.initials: SG
authors.lastname: Xiao
authors.forename: Xiao-liang
authors.initials: XL
authors.lastname: Yang
authors.forename: Zhen-wei
authors.initials: ZW
authors.lastname: Liu
mesh_terms: D002516:Ceramics / Q000737:chemistry*; D004735:Energy Transfer; D004871:Erbium / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D005459:Fluorides / Q000737:chemistry; D005461:Fluorine / Q000737:chemistry*; D049449:Luminescence; D010087:Oxides / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D014961:X-Ray Diffraction; D015018:Ytterbium / Q000737:chemistry
chemical_list: D005290:Ferric Compounds; D010087:Oxides; D005461:Fluorine; D012822:Silicon Dioxide; D004871:Erbium; C014559:fluorine monoxide; D015018:Ytterbium; D005459:Fluorides