Search for dissertations about: "natural sciences physics condensed matter physics mesoscopic physics"

Showing result 6 - 10 of 42 swedish dissertations containing the words natural sciences physics condensed matter physics mesoscopic physics.

  1. 6. Resonant switching and vortex dynamics in spin-flop bi-layers

    Author : Sergiy Cherepov; Vladislav Korenivski; Thomas Silva; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; spin-dynamics; MRAM; vortex; switching; Condensed matter physics; Kondenserade materiens fysik; Magnetism; Magnetism; Mesoscopic physics; Mesoskopisk fysik;

    Abstract : This thesis is a study of the static and dynamic behavior of the magne-tization in spin-flop bi-layers, which consist of two soft ferromagnetic layerscoupled by dipolar forces through a thin nonmagnetic spacer. The focus ofthe work is three fold: collective spin dynamics in the anti-parallel groundstate; resonant switching in the presence of thermal agitation; and static anddynamic behavior of the system in the vortex-pair state, with a particularemphasis on the interlayer core-core interaction. READ MORE

  2. 7. Tailoring the magnetic order in mesoscopic spin systems

    Author : Henry Stopfel; Vassilios Kapaklis; Hjörvarsson Björgvin; Unnar Arnalds; John Cumings; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; artificial spin ice; magnetic nano-structures; mesoscopic spin systems; mesospins; model systems; Shakti; Saint George; interaction modifier; engineering of energy-landscape; multiple energy-scales; Fysik; Physics;

    Abstract : Mesoscopic spin systems can be designed and fabricated using modern nano-fabrication techniques. These systems can contain large numbers of patterned ferromagnetic elements, for which the shape will generally determine their effective mesospin dimensionality. READ MORE

  3. 8. Mesoscopic thin film superconductors - A computational framework

    Author : Mikael Håkansson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Riccati equation; quasiclassical theory; simulation; GPU; time-reversal symmetry; CUDA; Eilenberger equation; coherence functions; Superconductivity; computational;

    Abstract : Motivated by experiments on superconductors in the microscopic regime and the realization of small superconducting devices such as qubits, we initiate a computational project in the form of a numerical simulation package to model and predict the behavior of these type of systems. It is a multidisciplinary endeavor in that it employs theory, computational science, software design, and to some extent new visualization techniques. READ MORE

  4. 9. Crystallization of the superconducting phase in unconventional superconductors

    Author : Patric Holmvall; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; pattern formation; spontaneous symmetry breaking; Andreev bound states; mesoscopic superconductivity; phase crystals; thin superconducting films; phase transitions; non-local Ginzburg-Landau theory; time-reversal symmetry; flat bands; unconventional superconductivity; quasiclassical theory; translational symmetry; cuprates; inhomogeneous superconductivity;

    Abstract : Superconductivity is a macroscopic quantum phenomenon, in the sense that a macroscopic number of electrons form a pair condensate, that occupies a single ground state. The electrons in this state are phase-coherent, breaking global U (1)-symmetry, and spatial variations of the phase imply superflows that usually cost kinetic energy, resulting in a uniform and rigid phase. READ MORE

  5. 10. Deriving effective forces for mesoscopic particle simulations

    Author : Johan Nyström; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Coarse graining; Boids; Force covariance; Mori-Zwanzig projection; Dissipative particle dynamics; Force matching; Flocking.;

    Abstract : In the field of molecular simulations, the long-standing aim has been to study mechanisms that cannot easily be observed in experiments or understood in terms of more abstract models. This is hard for systems of mesoscopic size (proteins, membranes etc. READ MORE