Search for dissertations about: "Phase transition"

Showing result 21 - 25 of 786 swedish dissertations containing the words Phase transition.

2. 21. Phase Transitions and Phase Formation of Hydrogen in Quasi-2D Lattices

   Author : Stefan Olsson; Björgvin Hjörvarsson; Yuh Fukai; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; hydrogen; finite-size effects; long-ranged interactions; superlattices; phase transitions; elastic interaction; Fysik; Physics; Fysik;

   Abstract : The role of the dimensionality and strain state of metallic lattices on the phase behavior of dissolved hydrogen was explored. Metallic superlattices with well defined hydrogen absorption potential on the nm scale, were utilized as test systems. READ MORE

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

   Author : Hannes Meier; Mats Wallin; Asle Sudbø; KTH; []
   Keywords : 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; Fysik; Physics;

   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. 23. Phase transitions in high-temperature superconductors

   Author : Jack Lidmar; KTH; []
   Keywords : Superconductivity; Vortices; Phase transitions; Strongly correlated fermions; High-temperature superconductivity; Monte Carlo simulations.; TECHNOLOGY; TEKNIKVETENSKAP;

   Abstract : Thermal fluctuations and disorder strongly influence the behaviour of hightemperature superconductors. In particular the vortices play a key role in determining their properties. In this thesis the main focus lies on phase transitions, both in ultra-thin films and in three-dimensional systems, which are driven by vortex fluctuations. READ MORE

6. 24. Hg Cuprate Superconductors Technological and Conceptual Tools

   Author : Rafael Gatt; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; mercury; high pressure; pulsed laser deposition; crystal growth; high temperature superconductors; cluster calculations; flat bands; thin oxide films; powder diffraction; structure refinement; phase transition; electronic structure; liquid phase epitaxy;

   Abstract : This work concerns superconductivity in the cuprates. It touches some of the problems that this field displays. As a representing case, the Hg based cuprates are chosen. READ MORE

7. 25. Atomistic simulation and experimental studies of transition metal systems involving carbon and nitrogen

   Author : Jiaying Xie; Seshadri Seetharaman; Oleg Ostrovski; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transition metal carbides; Transition metal nitrides; Transition metal carbo-nitrides; Lattice inversion method; Interatomic potential; Atomistic simulation; Metallurgical process engineering; Metallurgisk processteknik;

   Abstract : The present work was initiated to investigate the stability, structural and thermodynamic properties of transition metal carbides, nitrides and carbo-nitrides by atomistic simulations and experimentations. The interatomic pair potentials of Cr-Cr, Mn-Mn, Fe-Fe, C-C, Cr-C, Mn-C, Fe-C, Cr-Fe, Cr-N and Mn-N were inverted by the lattice inversion method and ab initio cohesive energies, and then employed to investigate the properties of Cr-, Mn- and Fe-carbides by atomistic simulations in this work. READ MORE