Search for dissertations about: "Natural rare-earth"

Showing result 1 - 5 of 101 swedish dissertations containing the words Natural rare-earth.

  1. 1. Coherent Processes in Rare-Earth-Ion-Doped Solids

    Author : Andreas Walther; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; quantum memories; laser stabilization; quantum computation; rare-earth-ion-doped crystals; spectral hole-burning; superradiance; entanglement; spectroscopy; slow light;

    Abstract : This thesis describes a number of coherent processes, such as quantum information processing, superradiance and electromagnetically induced transparency, which have been experimentally implemented using rare-earth-ion-doped crystals. The rare-earths are a class of elements that have in common, an atomic structure that allows for very long lifetimes as well as coherence times, both on optical transitions and on spin transitions. READ MORE

  2. 2. Studies of rare-earth tungsten oxides : synthesis, structures and phase/pressure relations

    Author : Carl Grenthe; Stockholms universitet; []

    Abstract : .... READ MORE

  3. 3. Transition Properties of f-electrons in Rare-earth Optical Materials

    Author : Daniel Åberg; Börje Johansson; Sverker Edvardsson; Lidia Smentek; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; Physics; rare-earth ions; oscillator strengths; correlation; crystal field; f-electrons; Fysik; Physics; Fysik;

    Abstract : The main purpose of this thesis is to theoretically study energy levels and intra-electronic transition intensities for various f-electron systems. The f-f electronic dipole transitions are parity-forbidden for a free ion but become non-zero when the ion is subject to a crystal-field. READ MORE

  4. 4. Hydrometallurgical recovery of rare earth elements from flourescent lamp waste fractions

    Author : Cristian Tunsu; Chalmers University of Technology; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; rare earth elements; recycling; fluorescent lamp waste; solvent extraction; waste treatment; Cyanex 572; leaching; Cyanex 923;

    Abstract : Recovery and reuse of materials is important for a circular economy. In recent years the recovery of critical metals from end-of-life products has received increased attention. Various streams, e.g. READ MORE

  5. 5. Radiative Properties of Rare Earth Elements - Free and Bound in Crystals

    Author : Huailiang Xu; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Laser Spectroscopy; Upconversion; Lifetimes; Atomic and molecular physics; Atom- och molekylärfysik; Laser technology; Laserteknik; Rare earth Elements; Fysicumarkivet A:2004:Xu;

    Abstract : This thesis is devoted to fundamental aspects, and to spectroscopic applications of radiative properties in free atoms and ions, as well as in ions doped into crystals. Using the time-resolved laser-induced fluorescence technique, measurements of radiative lifetimes for rare earth elements have been performed in neutral Pr, Nd, Tm, and in singly ionized Sm, Er, Nd, Tm, Yb, as well as in doubly ionized Tm and Tb ions. READ MORE