Search for dissertations about: "domain wall"

Showing result 16 - 20 of 126 swedish dissertations containing the words domain wall.

  2. 16. Hot-wall MOCVD for advanced GaN HEMT structures and improved p-type doping

    Author : Alexis Papamichail; Vanya Darakchieva; Anelia Kakanakova-Gueorguieva; Jr-Tai Chen; Zlatko Sitar; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Hot-wall MOCVD; III-nitrides; p-type GaN; HEMTs; Linearity; High-Al barrier;

    Abstract : The transition to energy efficient smart grid and wireless communication with improved capacity require the development and optimization of next generation semiconductor technologies and electronic device components. Indium nitride (InN), gallium nitride (GaN) and aluminum nitride (AlN) compounds and their alloys are direct bandgap semiconductors with bandgap energies ranging from 0. READ MORE

  4. 17. Ferromagnetic resonance in films with growth induced anisotropy

    Author : Sergey Manuilov; Alex Grishin; Boris Kalinikos; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ferromagnetic resonance; magnetic anisotropy; single-ion anisotropy model; ferrites; magnetic epitaxial films; magnetostatic waves; pulsed laser deposition; magnetic alloys; domains; domain wall transformations;

    Abstract : This thesis discusses two different magnetic materials: epitaxial yttrium iron garnet (YIG) and heteromorphous CoFeB-SiO2 films. YIG films were grown by pulse laser deposition (PLD) techniques onto gadolinium gallium garnet (GGG) substrates of (111) and (001) crystal orientations. READ MORE

  5. 18. Investigations of Flow Patterns in Ventilated Rooms Using Particle Image Velocimetry : Applications in a Scaled Room with Rapidly Varying Inflow and over a Wall-Mounted Radiator

    Author : Amir Sattari; Ivo Martinac; Mats Sandberg; Dirk Müller; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Particle Image Velocimetry PIV ; experimental study; structured light 3D scanning system; ventilation; varying flow rate; room model; wall-mounted radiator; air; water; flow; Particle Image Velocimetry PIV ; experimentell studie; scanningsystem för strukturerat 3D-ljus; ventilation; varierande tilluftsflöde; rumsmodell; väggmonterad radiator; Engineering Mechanics; Teknisk mekanik; Byggvetenskap; Civil and Architectural Engineering; Energy Technology; Energiteknik;

    Abstract : This thesis introduces and describes a new experimental setup for examining the effects of pulsating inflow to a ventilated enclosure. The study aimed to test the hypothesis that a pulsating inflow has potential to improve ventilation quality by reducing the stagnation zones through enhanced mixing. READ MORE

  6. 19. Coherent structures and control in wall-bounded turbulent flows

    Author : Marco Atzori; Philipp Schlatter; Ricardo Vinuesa; Oscar Flores; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent boundary layers; numerical simulations; coherent structures; predetermined flow control.; Turbulenta gränsskikt; numeriska simuleringar; koherenta strukturer; förutbestämd flödeskontroll; Teknisk mekanik; Engineering Mechanics;

    Abstract : This thesis is concerned with two distinct topics related to the study of wall-bounded turbulence: the connection between instantaneous three-dimensional coherent structures and mean-flow properties, and the development and analysis of pre-determined control techniques for adverse-pressure-gradient boundary layers.We examined regions with intense velocity fluctuations in various flowcases. READ MORE

  7. 20. Studies on Domain Dynamics in Nonlinear Optical Ferroelectric Oxide Crystals

    Author : Hoda Kianirad; Fredrik Laurell; Carlota Canalias; Sakellaris Mailis; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fysik; Physics;

    Abstract : Nonlinear optical frequency conversion is the key technology for modifying laser output radiation, in order to target specific applications. The most powerful technique to obtain tailored second-order nonlinear interactions is the quasi-phasematching (QPM) approach. READ MORE