Search for dissertations about: "rare earths"

Showing result 1 - 5 of 17 swedish dissertations containing the words rare earths.

2. 1. Internal magnetic fields in rare-earths and rare-earth compounds studied by PAC

   Author : Arnulf Mayer; Uppsala universitet; []
   Keywords : NATURAL SCIENCES; NATURVETENSKAP;

   Abstract : .... READ MORE

4. 2. Cohesive and Spectroscopic properties of the Lanthanides within the Hubbard I Approximation

   Author : Inka Laura Marie Locht; Igor Di Marco; Olle Eriksson; Annalisa Fasolino; Mikhail I. Katsnelson; Tim Wehling; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Lantanides; rare earths; cohesive properties; volume; bulk modulus; magnetism; magnetic properties; photoemission spectroscopy; XPS; BIS; Hubbard I Approximation; DMFT; DFT; RSPt; Full Potential Linear Muffin-tin orbitals; 4f electrons; localization; bonding; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Abstract : We describe the rare-earth elements using the Hubbard I approximation. We show that the theory reproduces the cohesive properties, like the volume and bulk modulus, and we find an excellent agreement between theory and experiment for the (inverse) photo emission spectra of the valence band. READ MORE

5. 3. Theoretical methods for the electronic structure and magnetism of strongly correlated materials

   Author : Inka L. M. Locht; Igor Di Marco; Silke Biermann; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; dynamical mean field theory DMFT ; Hubbard I approximation; strongly correlated systems; rare earths; lanthanides; photoemission spectra; ultrafast magnetization dynamics; analytic continuation; Padé approximant method; two-particle Green s functions; linear muffin tin orbitals LMTO ; density functional theory DFT ; cerium; stacking fault energy.; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Abstract : In this work we study the interesting physics of the rare earths, and the microscopic state after ultrafast magnetization dynamics in iron. Moreover, this work covers the development, examination and application of several methods used in solid state physics. The first and the last part are related to strongly correlated electrons. READ MORE

6. 4. 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

7. 5. Development of metal hydride surface structures for high power NiMH batteries : Also extended cycle-life and lead to more effective recycling methods

   Author : Yang Shen; Dag Noréus; Andreas Züttel; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Metal hydrides; NiMH batteries; Surface treatment; Ni clusters; Rare earths hydroxides; Oxygen; Hydrogen; Inorganic Chemistry; oorganisk kemi;

   Abstract : By combining alkaline etching of hydrogen storage alloys or their hydrides with a controlled oxidation, it was possible to improve reaction kinetics and accelerate activation of MH-electrodes. Both AB5 and AB2 alloys were studied where A is mixtures of rare earth elements for AB5 alloys and titanium and/or vanadium, zirconium for AB2 alloys; nickel contributes the major part of B. READ MORE