Search for dissertations about: "BRILLOUIN-ZONE"

Showing result 1 - 5 of 21 swedish dissertations containing the word BRILLOUIN-ZONE.

2. 1. Electronic structure and optical properties of PbY and SnY (Y=S, Se, and Te)

   Author : Nilton Souza Dantas; Clas Persson; Natalia Skorodumova; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Other materials science; Övrig teknisk materialvetenskap;

   Abstract : Lead chalcogenides and tin chalcogenides and their alloys are IV−VI family semiconductors with unique material properties compared with similar semiconductors. For instance, PbY (Y = S, Se, and Te) are narrow-gap semiconductors with anomalous negative pressure coefficient and positive temperature coefficient. READ MORE

4. 2. Hydrodynamics of Binary Bose-Einstein Condensates and Hydro-elasticity of the Inner Crust of Neutron Stars

   Author : Dmitry Kobyakov; Emil Lundh; Vitaly Bychkov; Mattias Marklund; Achim Schwenk; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Binary Bose-Einstein condensates in ultracold gases; hydrodynamics; quantum turbulence; neutron stars; the inner crust; nuclear astrophysics; fysik; Physics;

   Abstract : In the present thesis, “Hydrodynamics of Binary Bose-Einstein Condensates and Hydro-elasticity of the Inner Crust of Neutron Stars”, the hydrodynamic effects, instabilities and superfluid turbulence in binary immiscible ultracold gases, and hydro-elastic macroscopic coupled modes and microscopic structure of the inner layers of the crust of neutron stars, are studied. The ultracold gas dynamics can be realized in the laboratory. READ MORE

5. 3. Quantum Transport Theory in Graphene

   Author : Anders Bergvall; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; quantum coherent electron transport; nanoribbons; FT-LDOS; grain boundaries; tight-binding; graphene;

   Abstract : In this thesis, we focus on different aspects of electron transport in nanostructured graphene (such as graphene nanoribbons). Wedevelop and implement numerical methods to study quantum coherent electron transport on an atomistic level, complemented by analytical calculations based on the Dirac approximation valid close to the points $\vec{K}$ and $\vec{K}^\prime$ in the graphene Brillouin zone. READ MORE

6. 4. Materials for Magnetic Recording Applications

   Author : Till Burkert; Olle Eriksson; Lars Nordström; Stefan Blügel; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; magnetic materials; magnetic anisotropy; saturation magnetization; magnetic data storage; superlattice; hydrogen; density functional theory; first-principles calculations; two-dimensional magnetism; FP-LMTO; EXAFS; MOKE; Fysik; Physics; Fysik;

   Abstract : In the first part of this work, the influence of hydrogen on the structural and magnetic properties of Fe/V(001) superlattices was studied. The local structure of the vanadium-hydride layers was determined by extended x-ray absorption fine structure (EXAFS) measurements. READ MORE

7. 5. Theoretical Studies of Magnetism and Electron Correlation in Solids

   Author : Oscar Grånäs; Lars Nordström; Biplab Sanyal; Silke Biermann; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Magnetism; Superconductivity; Electron Correlation; DMFT; DFT; Actinides; multipoles; hidden order; magnetic anisotropy; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Abstract : This work presents new development and applications of ab-initio simulation tools for material science. Focus lies on materials with strong electronic correlation and strong spin-orbit coupling. READ MORE