Search for dissertations about: "phonon"

Showing result 1 - 5 of 155 swedish dissertations containing the word phonon.

  1. 1. Quantum acoustics with propagating phonons

    Author : Maria Ekström; Chalmers University of Technology; []
    Keywords : NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; phonon router; phonon; quantum acoustics; interdigital transducer; Electromagnetically Induced Transparency; artificial atom; Surface acoustic wave; superconducting circuits; qubit; unidirectional transducer;

    Abstract : Surface acoustic waves (SAWs) are mechanical vibrations that propagate on the surface of solids while dissipating little power, consequently enabling them to propagate freely over long distances. The speed and wavelength of SAWs are reduced a five order of magnitude compared to when light is used as a carrier at gigahertz frequencies. READ MORE

  2. 2. Materials Design from ab initio Calculations

    Author : Sa Li; Börje Johansson; Rajeev Ahuja; Gilles Hug; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; Physics; DFT; MAX; Optics; phase transition; phonon; EOS; Fysik; Physics; Fysik;

    Abstract : This thesis presents a theoretical study of bulk materials using ab initio methods based on the density functional theory (DFT).Crystallographic structural phase transformations and phase stability for 5f-dioxides, ABO3 perovskites, and ABO4 compounds have been extensively studied. READ MORE

  3. 3. Experimental Studies of Thermal Diffusivities concerning some Industrially Important Systems

    Author : Riad Abdul Abas; Seshadri Seetharaman; Rainer Wunderlich; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; laser flash; thermal diffusivity; heat conduction; phonon; electron contribution; crystallisation degree; graphitisation; Metallurgical process engineering; Metallurgisk processteknik;

    Abstract : The main objective of this industrially important work was to gain an increasing understanding of the properties of some industrially important materials such as CMSX-4 nickel base super alloy, 90Ti.6Al.4V alloy, 25Cr:6Ni stainless steel, 0. READ MORE

  4. 4. Towards measuring quantum sound

    Author : Maria Ekström; Chalmers University of Technology; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; surface acoustic wave; interdigital transducer; artificial atom; qubit; superconducting circuits; cryogenic temperature; phonon; gigahertz frequency; quantum acoustics; unidirectional transducer;

    Abstract : One of the most fundamental phenomena occurring in nature is the interaction between single atoms and electromagnetic fields. This is studied in quantum optics to probe the quantum nature of the system. In appended Paper I, we demonstrated that an artificial atom can couple to propagating sound, which is the acoustic analogue of quantum optics. READ MORE

  5. 5. Studies of Phonons and Phase Transitions by Time-Resolved X-ray Diffraction

    Author : Henrik Enquist; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; synchrotron radiation; ultrashort pulses; material science; phase transition; X-ray diffraction; phonon; X-ray detector;

    Abstract : When light is used to study structures, the wavelength limits the size of the details that can be resolved. Visible light can be used to investigate structures as small as a micrometre in size. To study smaller structures a shorter wavelength is required. READ MORE