Search for dissertations about: "Rare-earth ions"

Showing result 1 - 5 of 32 swedish dissertations containing the words Rare-earth ions.

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

   Author : Daniel Åberg; Börje Johansson; Sverker Edvardsson; Lidia Smentek; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; 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. 2. Quantum Optics and Quantum Information Processing in Rare-Earth-Ion-Doped Crystals

   Author : Nicklas Ohlsson; Atomfysik; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Rare-earth ions; Optical processing; Optical storage; Electromagnetism; akustik; optik; Elektromagnetism; optics; acoustics; Photon echo; Quantum optics; Quantum computing; Fysicumarkivet A:2003:Ohlsson;

   Abstract : In this thesis, aspects of the use of cryogenically cooled rare-earth-ion-doped crystals in the fields of quantum optics and quantum information processing are addressed. The experiments and theoretical considerations referred to in this thesis are based on the coherent transient interaction between light and the ions in the crystals. READ MORE

5. 3. Coherent Processes in Rare-Earth-Ion-Doped Solids

   Author : Andreas Walther; Atomfysik; []
   Keywords : 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

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

   Author : Huailiang Xu; Atomfysik; []
   Keywords : 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

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

   Author : Cristian Tunsu; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; 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