Sökning: "phonons"

Visar resultat 1 - 5 av 71 avhandlingar innehållade ordet phonons.

  1. 1. Raman scattering investigations of phonons in ceramic high-T superconductors

    Författare :Mikael Käll; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; charge distribution; Raman spectroscopy; high-Tc superconductors; ceramics; phonons; atomic substitution;

    Sammanfattning : .... LÄS MER

  3. 2. Time-resolved X-ray diffraction studies of phonons and phase transitions

    Författare :Ola Synnergren; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Fysik; Physics; Phase transitions; X-ray diffraction; Phonons; X-ray diffraction;

    Sammanfattning : This thesis summarizes work in which time-resolved X-ray diffraction has been used to probe crystalline materials, thereby revealing the dynamics of phonons and phase transitions. X-ray diffraction is the standard tool in investigations of structure on the atomic scale. LÄS MER

  4. 3. Beyond Perturbation: Modeling Anharmonicity in Materials

    Författare :Fredrik Eriksson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Molecular Dynamics; Force Constants; Lattice Thermal Conductivity; Green-Kubo; Peierls-Boltzmann Transport Equation; Lattice dynamics; Phonons; Anharmonicity;

    Sammanfattning : The vibrational motion of atoms is essential for understanding condensed matter systems. It directly influences numerous thermodynamic properties with significant technological implications. LÄS MER

  5. 4. Significance of grain boundaries for transport phenomena in graphene and proton-conducting barium zirconate

    Författare :Edit Ahlberg Helgee; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; graphene; density functional theory; phonons; proton conduction; grain boundaries; BaZrO3; interatomic model potentials;

    Sammanfattning : Grain boundaries can have a significant influence on the properties of polycrystalline materials. When determining the type and extent of this influence it is frequently useful to employ computational methods such as density functional theory and molecular dynamics, which can provide models of the grain boundary structure at the atomistic level. LÄS MER

  7. 5. Raman Scattering Studies of High-Tc Superconductors

    Författare :Mikael Käll; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; superconducting gap; phonons; Raman scattering; high-Tc superconductivity;

    Sammanfattning : This thesis describes Raman scattering investigations of cuprate high-Tc superconductors. The objective is to gain further knowledge on the physical properties that are relevant for the appearance of high-Tc superconductivity. LÄS MER