Search for dissertations about: "quantum mechanics"

Showing result 21 - 25 of 187 swedish dissertations containing the words quantum mechanics.

  2. 21. Probing Magnetism at the Atomic Scale:  Non-Equilibrium Statistical Mechanics Theoretical Treatise

    Author : Juan David Vasquez Jaramillo; Jonas Fransson; Rosa Lopez; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Non-Equilibrium Statistical Mechanics; Magnetism; Quantum Optics; Quantum Coherence; RKKY; Colciencias; Equation of Motion; Jauho-Meir-Wingreen Formalism; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik; Physics with specialization in Quantum Chemistry; Fysik med inriktning mot kvantkemi; Physics and Astronomy specializing in Theoretical Physics; Fysik och astronomi med inriktning mot teoretisk fysik;

    Abstract : Here, I present a theoretical study, based on non-equilibrium quantum statistical mechanics and on the non-equilibrium extension to the RKKY intveraction,where I investigate the emergence of magnetism at the atomic scale in adsorbed molecular complexes hosting localized spin moments, at the stake of being probed with scanning tunneling microscopy tip, and being driven by a temperature gradient and gated by an electric field. The scanning tunneling microscopy set up is modeled as a molecular junction with a magnetic molecule embedded within it, where the molecule consists in a set of electronic levels resembling the typical s-p orbitals of a metal hydride or an organometal, and a localized spin moment resembling the magnetic unit hosted by the latter and former type of molecules mentioned. READ MORE

  4. 22. Controllable coupling of superconducting qubits and implementation of quantum gate protocols

    Author : Margareta Wallquist; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Controllable Qubit-Coupling; Single Cooper-Pair Box; Josephson Effect; Quantum Gate; Superconducting Circuit; Quantum Computer; Qubit; Quantum Electrical Circuit;

    Abstract : The concept of a quantum computer was invented in the beginning of the 1980s as a quantum generalization of the reversible classical computer. After discoveries in the middle of the 1990s of quantum algorithms, which wouldsolve some problems considered intractable for classical computers, the field of quantum computing has developed rapidly. READ MORE

  5. 23. Isospin Breaking in Kaon Decays to Pions

    Author : Fredrik Borg; Teoretisk partikelfysik - Geonomgår omorganisation; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Elementary particle physics; termodynamik; statistisk fysik; gravitation; relativitet; kvantmekanik; thermodynamics; Matematisk och allmän teoretisk fysik; Pseudo-scalar meson; Isospin Breaking; Chiral Perturbation Theory; Mathematical and general theoretical physics; classical mechanics; quantum mechanics; relativity; statistical physics; Weak Interaction; Strong Interaction; kvantfältteori; High energy interactions; Kärnfysik; Nuclear physics; klassisk mekanik; quantum field theory; cosmic rays; Kosmisk strålning; högenergi; Elementarpartikelfysik;

    Abstract : The five different K -> 3 Pi and the three K -> 2 Pi decays are calculated in Chiral Perturbation Theory. The calculation is done using different approximations, to study whether this changes the result significantly. First the isospin approximation is used. Discrepancies are then found between theory and experiment. READ MORE

  6. 24. Some Aspects of Chirality: fermion masses and chiral p-forms

    Author : Astri Kleppe; Matematisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; relativitet; kvantmekanik; klassisk mekanik; Matematisk och allmän teoretisk fysik; massive neutrinos; fermion masses; Mathematical and general theoretical physics; self-dual fields; democratic family mixing; quantum mechanics; classical mechanics; relativity; gravitation; thermodynamics; statistical physics; statistisk fysik; termodynamik; Elementary particle physics; quantum field theory; Elementarpartikelfysik; kvantfältteori; Fysicumarkivet A:1997:Kleppe;

    Abstract : This thesis deals with different types of chiral fields. The properties of fermion masses are investigated from different poits of view, both within the Standard Model and in extensions of the model. It is shown how mass matrix invariants are used to define the measurables of the quark mixing matrix as invariant functions of the mass matrices. READ MORE

  7. 25. Resonant states in modulation-doped heterostructures

    Author : Anders Blom; Matematisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mathematical and general theoretical physics; generation-recombination noise; THz laser; classical mechanics; relativity; quantum mechanics; statistisk fysik; gravitation; relativitet; kvantmekanik; klassisk mekanik; Matematisk och allmän teoretisk fysik; thermodynamics; termodynamik; statistical physics; donor energies; Si SiGe quantum well; central-cell effect; impurity absorption; Fysicumarkivet A:2003:Blom; Resonant states; impurity levels;

    Abstract : This thesis deals with the properties of donors placed inside or outside a heterostructure quantum well (QW). The focus of the investigation has been on the formation of resonant states, which are a hybridization of the discrete localized impurity levels and the continuous two-dimensional QW subbands. READ MORE