Search for dissertations about: "many-electron effects"

Found 4 swedish dissertations containing the words many-electron effects.

  2. 1. Diagrammatic many-body theory for atoms in high-intensity laser fields

    Author : Lars Jönsson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; high-intensity laser-atom interaction; multiphoton processes; photoelectron spectra; Floquet states; many-electron effects; Diagrammatic many-body theory;

    Abstract : .... READ MORE

  4. 2. Effects of Spin-Orbit Interactions in Ferromagnetic Metal Nanoparticles

    Author : Aleksander Cehovin; Matematisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; electrical; magnetic and optical properties; elementary spin excitations; spektroskopi; magnetisk resonans; supraledare; electron tunneling spectroscopy; Condensed matter:electronic structure; magnetic anisotropy; spin-orbit interactions; magnetism in nanostructures; egenskaper elektriska; ferromagnetic materials; magnetiska och optiska ; Kondenserade materiens egenskaper:elektronstruktur; relaxation; spectroscopy; supraconductors; magnetic resonance; Fysicumarkivet A:2003:Cehovin;

    Abstract : This thesis is a theoretical investigation of the effects of spin-orbit (SO) interactions in ferromagnetic metal nano-particles. Part I of the thesis is devoted to an elementary introduction of the research field, including recent experimental advances which partly motivated the work presented here. READ MORE

  5. 3. Theoretical Developments for the Real-Time Description and Control of Nanoscale Systems

    Author : Miroslav Hopjan; Matematisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Green’s Function; DFT; TDDFT; Hubbard Model; Many-Body Perturbation Theory; Strongly Correlated Systems; Quantum Transport; Disorder; Ehrenfest Dynamics; Electronic Friction; Exact Diagonalization; Periodic Anderson Model; Fysicumarkivet A:2018:Hopjan;

    Abstract : In this thesis we focus on improvements of the description of the electron-electron correlation effects in nonequilibrium nanosystems. We mainly focus on developments of two nonequilibrium methods, namely the formalism of Nonequilibrium Green’s Function and Time Dependent Density Functional Theory and we explore the possibility to improve existing approximations in these theories. READ MORE

  6. 4. Role of charge and spin fluctuations and their interplay in solids : A Green’s function approach

    Author : Tor Sjöstrand; Matematisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Green’s function; correlations; collective excitations; screened interaction; electric polarization; orbital and spin magnetization; magnon-phonon interaction; Fierz ambiguity; time-dependent exchange-correlation potential;

    Abstract : Due to the large number of electrons, solid state physics boils down to many-body approximations in which only selected types of collective excitations are taken into account, guided by the emergent properties of the material under study. In this thesis, the collective excitations of primary interest are electronic charge and spin fluctuations(plasmons and magnons) and nuclear charge fluctuations (phonons). READ MORE