<link rel="stylesheet" href="styles.cf390c6bfbe7555f.css">

學術出版;;Publications

Permanent URI for this communityhdl:11536/1

收集所有交通大學研究人員與學生個人或團體所發表之各項學術著作，涵蓋期刊論文、教師專書、學位論文等項。;;Collections of Publications of NCTU Researchers and Students Like Journal Papers and Thesis.

Browse

Filters

2009 - 20102

Settings

🏛️國立陽明交通大學機構典藏

Author: search.filters.author.Hsieh, Wen-FengSubject: search.filters.subject.X-ray diffraction

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item type:Item,
    Er-Yb Codoped Ferroelectrics for Controlling Visible Upconversion Emissions
    (2009-05-01)
    Huang, Tung-Ching
    ;
    Hsieh, Wen-Feng
    ;
    光電工程學系
    ;
    Department of Photonics
    Under a 980 nm laser pumping, quenching of green upconversion (UC) emission accompanied with enhancement of red UC emission observed was dominated by the energy back-transfer (EBT) process in Er(3+) and Yb(3+) codoped PbTiO(3), BaTiO(3), and SrTiO(3) polycrystalline powders. The efficiency of the EBT process depends not only on Yb(3+) concentration but also on level match of the doped Er(3+) and Yb(3+) ions caused by the crystal fields with different symmetries. Our UC emission spectra and X-ray diffraction confirm that the centrosymmetric crystal field arising from reducing tetragonality causes level match of transition (4)S(3/2) -> (4) I(13/2) of Er(3+) and (2)F(7/2) -> (2) F(5/2) of Yb(3+). This level match is responsible for enhancing red UC emission.
  • Thumbnail Image
    Item type:Item,
    Destruction of the short-range disorder due to erbium doping in Pb(0.8)La(0.2)TiO(3)films
    (2010-05-01)
    Huang, Tung-Ching
    ;
    Hsieh, Wen-Feng
    ;
    光電工程學系
    ;
    Department of Photonics
    We show the destruction of a displacement of Ti in the short-range structure by observing the disappearance of emission and Raman signals when the Er(3+) concentration exceeds 7 mol% in sol-gel-derived Pb(0.8)La(0.2)TiO(3) polycrystalline films. It is believed that there always exists disorder due to displacement of B ions in the skeleton of BO(6) in perovskite ABO(3) materials. This disorder due to the displacement of Ti ions breaks the center of symmetry to activate emission of rare-earth ions such as Er(3+) and Raman modes of perovskites. We found that the breaking of symmetry can be diminished by introducing more Er(3+) ions. Copyright (C) 2009 John Wiley & Sons, Ltd.