Sökning: "ultracold atoms"

Visar resultat 1 - 5 av 11 avhandlingar innehållade orden ultracold atoms.

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

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

    Sammanfattning : 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. LÄS MER

  3. 2. Ultracold rubidium atoms in periodic potentials

    Författare :Robert Saers; Anders Kastberg; Svante Jonsell; Jan W. Thomsen; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bose-Einstein condensation; optical lattice; quantum phase transition; experiment; theory; Condensed matter physics; Kondenserade materiens fysik;

    Sammanfattning : This thesis includes both experimental and theoretical investigations, presented in a series of eight papers. The experimental part ranges from the construction procedures of an apparatus for Bose-Einstein condensates, to full scale experiments using three different set-ups for ultracold atoms in optical lattices. LÄS MER

  4. 3. Experimental and Numerical Investigations of Ultra-Cold Atoms

    Författare :Magnus Rehn; Anders Kastberg; Claude Dion; Matti Kaivola; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ultracold atoms; optical lattices; Bose-Einstein condensation; quantum phase transitions; Physics; Fysik;

    Sammanfattning : I have been one of the main responsible for building a new laboratory for Bose-Einstein condensation with 87Rb. In particular, the experimental setup has been designed for performing experiments with Bose-Einstein condensates load into optical lattices of variable geometries. All parts essential for Bose-Einstein condensation are in place. LÄS MER

  5. 4. Many-photon effects in time-resolved second harmonic generation from systems in optical cavities

    Författare :Megha Gopalakrishna; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Second harmonic generation; Cavity optics; Non-linear optics; Cavity leakage; Ultracold atoms; Dicke model; Exact diagonalization; Non-equilibrium Green s functions; Fysicumarkivet A:2024:Gopalakrishna;

    Sammanfattning : Second harmonic generation is popular due to its numerous applications in different technologies dealing with multiple fields of science. The rapid technical advancement with the second harmonic generation demands parallel development in the theoretical understanding. LÄS MER

  7. 5. Three-body Universality Controlled by a Feshbach Resonance

    Författare :Kajsa-My Tempest; Svante Jonsell; Doerte Blume; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Efimov states; few-body systems; ultracold atoms; van der Waals interaction; Feshbach resonances; universality; computational studies; Theoretical Physics; teoretisk fysik;

    Sammanfattning : The quantum Efimov effect manifests itself in the limit of resonant two-body interactions, where the scattering length diverges. In this scenario, an infinite number of shallow bound trimer states are formed with binding energies that obey a discrete geometric scaling law. LÄS MER