Sökning: "local density of states"

Visar resultat 1 - 5 av 66 avhandlingar innehållade orden local density of states.

1. 1. Electronic states of adsorbates and insulating overlayers on metal surfaces

   Författare :Fredrik Olsson; Chalmers University of Technology; []
   Nyckelord :Shockley surface states; local density of states; scanning tunneling microscope; chemisorption; sodium chloride; noble metals; image states; electronic states; density functional theory;

   Sammanfattning : Electronic states of adsorbates and insulating overlayers provide a wealth of scientifically interesting phenomena with great technological importance. Interesting phenomena arise, for example, from the interaction of electronic states of an adsorbate with the continuum of metal electron states, both propagating bulk states and surface states. LÄS MER

3. 2. Microscopic Theory of Externally Tunable Exciton Signatures of Two-Dimensional Materials

   Författare :Maja Feierabend; Chalmers University of Technology; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; localized states; density matrix formalism; magnetic field; transition metal dichalcogenides; Bloch equations; organic inorganic heterostructures; dark excitons; strain;

   Sammanfattning : Atomically thin transition metal dichalcogenides (TMDs) are in the focus of current research due to their efficient light-matter interaction and the remarkably strong Coulomb interaction that leads to tightly bound excitons. Due to their unique band structure, TMDs show a variety of bright and optically inaccessible dark excitonic states. LÄS MER

4. 3. Nonlocal Correlations in Density Functional Theory

   Författare :Henrik Rydberg; Chalmers University of Technology; []
   Nyckelord :bonding; GGA; adhesion; graphene; DFT; exchange; adsorption; LDA; first principles; polarization; vdW; determinants; correlation; graphite; surface states; van der Waals; density-functional theory; physisorption; nonlocal; functional;

   Sammanfattning : In Density Functional Theory, the widely used local and semilocal approximations to the exchange-correlation energy, the local density approximation (LDA) and the generalized gradient approximations (GGAs), lack a physical description of truly nonlocal correlation effects, which are absolutely essential for a proper description of soft matter. A scheme is proposed that provides a basis for systematic improvements beyond LDA and GGA, including correlations at intermediate and long range, giving rise to bonds of pure van der Waals type as well as more intricate, intermediate-range correlation bonds. LÄS MER

5. 4. Correlated Electronic Structure of Materials : Development and Application of Dynamical Mean Field Theory

   Författare :Patrik Thunström; Olle Eriksson; Alexander Lichtenstein; Uppsala universitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; DFT; DMFT; correlation; entanglement; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Sammanfattning : This thesis is dedicated to the development, implementation and application of a combination of Density Functional Theory and Dynamical Mean Field Theory. The resulting program is shown through several examples to be a powerful and flexible tool for calculating the electronic structure of strongly correlated materials. LÄS MER

7. 5. Application of cluster calculations for the interpretation of electron and ion emission from ionic crystals

   Författare :Erik Westin; Chalmers University of Technology; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; local density approximation LDA ; laser induced desorption; alkaline-earth halogens; surface states; ionic crystals; electronic structure;

   Sammanfattning : .... LÄS MER