Search for dissertations about: "superfluidity"

Showing result 1 - 5 of 6 swedish dissertations containing the word superfluidity.

  1. 1. Ultracold atoms in optical potentials : from noise-induced transport to superfluidity

    Author : Martin Zelan; Claude Dion; Sile Nic Chormaic; Umeå universitet; []
    Keywords : Brownian motors; noise-induced transport; superfluidity; ultracold atoms; optical potentials; optical lattices; laser coooling; fysik; Physics;

    Abstract : In this thesis, both experimental studies and numerical simulations of ultracold atoms in optical potentials are presented in a collection of nine scientific papers. In particular, noise-induced transport in dissipative optical lattices and superfluid properties of Bose-Einstein condensates have been studied. READ MORE

  2. 2. Vortices and Persistent Currents in Rotating Bose Gases - a Diagonalization Approach

    Author : Sara Bargi; Matematisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Bose-Einstein condensation; vortices; superfluidity; Fysicumarkivet A:2010:Bargi;

    Abstract : In this thesis, I explore the behavior of rotating ultra-cold Bose gases, by diagonalizing the Hamiltonian. This method has the advantage of being exact in the limit of weak interactions, and thus is a useful complement to the more commonly used Gross-Pitaevskii (GP) equation, which relies on a mean-field approximation. READ MORE

  3. 3. Bose-Einstein Condensation of Magnetic Excitons in Semiconductor Quantum Wells

    Author : Vitalie Boţan; Lars Nordström; Sveatoslav Moskalenko; Pavlos Lagoudakis; Uppsala universitet; []
    Keywords : Physics; Bose-Einstein condensation; magnetic excitons; electron-hole pairs; electron-hole liquid; magnetorotons; magnetoplasmons; superfluidity; Fysik;

    Abstract : In this thesis regimes of quantum degeneracy of electrons and holes in semiconductor quantum wells in a strong magnetic field are studied theoretically. The coherent pairing of electrons and holes results in the formation of Bose-Einstein condensate of magnetic excitons in a single-particle state with wave vector K. READ MORE

  4. 4. Phase transitions in novel superfluids and systems with correlated disorder

    Author : Hannes Meier; Mats Wallin; Asle Sudbø; KTH; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; condensed matter physics; phase transitions; critical phenomena; spin models; quantum phase transitions; quantum fluids; superfluidity; superconductivity; disordered systems; Bose glass; dirty bosons; vortex pinning; statistical mechanics; Monte Carlo simulation; Wolff algorithm; classical worm algorithm; Wang-Landau algorithm; Physics; Fysik;

    Abstract : Condensed matter systems undergoing phase transitions rarely allow exact solutions. The presence of disorder renders the situation  even worse but collective Monte Carlo methods and parallel algorithms allow numerical descriptions. READ MORE

  5. 5. Structure formation, phase transitions and drag interactions in multicomponent superconductors and superfluids

    Author : Karl Sellin; Egor Babaev; Anatoly Kuklov; KTH; []

    Abstract : Superconductivity and superfluidity are some of the most funda-mental and important phenomena of modern physics. However, muchtheoretical work for such systems so far has been restricted to the one-component case. READ MORE