Sökning: "Quantum mechanical effects"

Visar resultat 36 - 40 av 67 avhandlingar innehållade orden Quantum mechanical effects.

1. 36. Criticality and Frustration: Classical and Quantum Spin Models in Two Dimensions

   Författare :Per Fröjdh; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : We investigate two-dimensional spin models and begin with an introduction to critical phenomena with emphasis on classical systems with boundaries and conformal invariance. Then we introduce the antiferromagnetic quantum Heisenberg model with frustrating interactions. LÄS MER

3. 37. Relativistic effects in Compton scattering of photons from bound electron states

   Författare :A. Roland Ribberfors; Linköpings universitet; []
   Nyckelord :;

   Sammanfattning : What is light? A correct answer to this question is: I don't know, but I can see some of its properties"! It is exciting to study such a complex thing and to search for models which can help us to try to understand, in a proper way, some of the most interesting behavior of light. We see the sunshine and the radiation makes us warm, undoubtly it must be some kind of energy? Interference experiments with monochromatic light show that the radiation has wave-like properties, but for example scattering experiments predict a particle nature. LÄS MER

4. 38. Theoretical studies of chemical dynamics on excited states, driven by non-adiabatic effects : Charge recombination reactions

   Författare :Sifiso Musa Nkambule; Åsa Larson; Adam Kirrander; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mutual neutralization; Dissociative recombination; electronic structure; non-adiabatic; teoretisk fysik; Theoretical Physics;

   Sammanfattning : This thesis is based on theoretical studies of molecular collisions occurring at relatively low to intermediate collision energies. The collisions are called dissociative recombination (DR) and mutual neutralization (MN). LÄS MER

5. 39. Magneto-optical studies of dilute nitrides and II-VI diluted magnetic semiconductor quantum structures

   Författare :Daniel Dagnelund; Irina Buyanova; Weimin Chen; Marek Godlewski; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Dilute nitrides; DMS; defect; ODMR; optically detected magnetic resonance; spin injection; PLE; photoluminescence excitation; post-growth hydrogenation; heterojunction; Semiconductor physics; Halvledarfysik;

   Sammanfattning : This thesis work aims at a better understanding of magneto-optical properties of dilute nitrides and II-VI diluted magnetic semiconductor quantum structures. The thesis is divided into two parts. The first part gives an introduction of the research fields, together with a brief summary of the scientific results included in the thesis. LÄS MER

7. 40. Surface and Interface Studies of ZnO using Reactive Dynamics Simulation

   Författare :David Raymand; Kersti Hermansson; Daniel Spångberg; Kai Nordlund; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; catalysis; molecular dynamics; force-fields; metal oxide; ZnO; dynamical effects on reactivity; Inorganic chemistry; Oorganisk kemi; Kemi med inriktning mot oorganisk kemi; Chemistry with specialization in Inorganic Chemistry;

   Sammanfattning : About 90% of all chemicals are produced with the help of catalysts, substances with the ability to accelerate reactions without being consumed. Metal oxides play a prominent role in catalysis, since they are able to act reversibly in many chemical processes. Zink oxide (ZnO) is used to catalyse a number of industrially important reactions. LÄS MER