Sökning: "Cuprates"

Visar resultat 16 - 20 av 26 avhandlingar innehållade ordet Cuprates.

1. 16. The paramagnetic Meissner effect

   Författare :Evie Papadopoulou; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; high-temperature superconductivity; Bi-based compounds; paramagnetic Meissner effect; ageing; disordered magnets; chiral-glass; Materialvetenskap; Materials science; Teknisk materialvetenskap; Solid State Physics; fasta tillståndets fysik;

   Sammanfattning : The low field dynamics of some high temperature superconductors have been studied experimentally, using SQUID magnetometry. The research has been focused on the so called Paramagnetic Meissner Effect (PME), a phenomenon seen in some high temperature superconducting cuprates. LÄS MER

3. 17. Metal Mediated Synthesis. Synthetic and Mechanistic Investigations of Conjugate Addition and Reductive Amination

   Författare :Anders Johansson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; halosilane; all-trans-geranylgeraniol; copper reagent; primary amines; S -geranylcitronellol; iminium salt; alfa; cuprate; beta-unsaturated; lithium iodide; borane dimethyl sulfide complex; reductive amination; conjugate addition;

   Sammanfattning : The thesis is divided into two separate parts, one treating conjugate addition and the other reductive aminations. The first part of the thesis is concerned with organocopper promoted conjugate addition to .alfa.,. LÄS MER

4. 18. Unifying first-principles and model approaches for strongly correlated materials : Interplay between long- and short-range correlations

   Författare :Fredrik Nilsson; Matematisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; first-principle methods; strongly correlated materials; GW approximation; cRPA; random-phase approximation; dynamical mean-field theory; GW DMFT; downfolding;

   Sammanfattning : In materials with open 3$d$ and 4$f$ shells the valence electrons are relatively localized around the atoms which leads to large electron-electron correlations. These, so called strongly correlated materials, exhibit many intriguing properties such as high $T_c$ superconductivity, colossal magneto-resistance and heavy fermion behaviour. LÄS MER

5. 19. Resonant Soft X-Ray Emission Spectroscopy of Vanadium Oxides and Related Compounds

   Författare :Thorsten Schmitt; Joseph Nordgren; Laurent Duda; Stefan Eisebitt; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; vanadium oxides; Li-battery; cathode materials; copper oxides; soft X-ray absorption; soft X-ray emission; resonant inelastic X-ray scattering; cluster model calculations; Fysik; Physics; Fysik;

   Sammanfattning : This thesis addresses the electronic structure of vanadium and copper oxides using soft X-ray absorption (SXA) spectroscopy and resonant inelastic X-ray scattering (RIXS) at high brightness synchrotron radiation sources. In RIXS incident photons, tuned to the energy of specific absorption resonances, are inelastically scattered leaving behind a low energy valence excitation in the system studied. LÄS MER

7. 20. Superradiant THz wave emission from arrays of Josephson junctions

   Författare :Ievgenii Borodianskyi; Vladimir Krasnov; Yury Shukrinov; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Josephson junction; Superconductor; ThZ emission; high-Tc; Physics; fysik;

   Sammanfattning : High-power, continuous-wave, compact and tunable THz sources are needed for a large variety of applications. Development of power-efficient sources of electromagnetic radiation in the 0.1-10 THz range is a difficult technological problem, known as the “THz gap. LÄS MER