Search for dissertations about: "Quantum rings"

Showing result 1 - 5 of 21 swedish dissertations containing the words Quantum rings.

2. 1. On the role of the electron-electron interaction in two-dimensional quantum dots and rings

   Author : Erik Waltersson; Eva Lindroth; Stephanie Reimann; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; quantum dot; quantum ring; quantum dot molecule; electronic structure; two-dimensional; many-body physics; many-body perturbation theory; coupled cluster; coupled cluster singles and doubles; quantum logical gates; quantum computing; quantum control; quantum control algorithm; Electronic structure; Elektronstruktur; fysik; Physics;

   Abstract : Many-Body Perturbation Theory is put to test as a method for reliable calculations of the electron-electron interaction in two-dimensional quantum dots. We show that second order correlation gives qualitative agreement with experiments on a level which was not found within the Hartree-Fock description. READ MORE

4. 2. Quantum Chemical Studies of Radical Cation Rearrangement, Radical Carbonylation, and Homolytic Substitution Reactions

   Author : Daniel Norberg; Nessima Salhi-Benachenhou; Sten Lunell; Tim Clark; Uppsala universitet; []
   Keywords : Quantum chemistry; quantum chemistry; coupled-cluster; density functional theory; meta-GGA; reaction mechanism; potential energy surface; isomerization; fragmentation; dissociation; condensation; addition; SH2; hydrogen abstraction; iodine atom transfer; complex; weakly interacting system; hyperfine coupling constant; Kvantkemi;

   Abstract : Quantum chemical calculations have been performed to investigate radical cation rearrangement, radical carbonylation, and homolytic substitution reactions of organic molecules. The rearrangement of the bicyclopropylidiene radical cation to the tetramethyleneethane radical cation is predicted to proceed with stepwise disrotatory opening of the two rings. READ MORE

5. 3. Many-Body effects in Semiconductor Nanostructures

   Author : Carl-Johan Wesslén; Eva Lindroth; Morten Førre; Stockholms universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; coupled cluster; nanostructure; quantum dot; quantum ring; concentric quantum ring; many body pertubation theory; fysik; Physics;

   Abstract : Low dimensional semiconductor structures are modeled using techniques from the field of many-body atomic physics. B-splines are used to create a one-particle basis, used to solve the more complex many-body problems. READ MORE

6. 4. Experiments on mutual neutralization using storage rings with merged ion beams

   Author : Gustav Eklund; Henning T Schmidt; Henrik Cederquist; Ansgar Simonsson; Daniel W. Savin; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; mutual neutralization; storage rings; merged beams; fysik; Physics;

   Abstract : This thesis presents work on merged-beams experiments using the DESIREE facility, which consists of two electrostatic ion-storage rings operated at cryogenic temperatures of about 13 K. The two storage rings have a common straight section, where oppositely charged ions can interact at sub-eV collision energies. READ MORE

7. 5. Confinement Sensitivity in Quantum Dot Spin Relaxation

   Author : Carl Wesslén; Eva Lindroth; Andrei Manolescu; Stockholms universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; fysik; Physics;

   Abstract : Quantum dots, also known as artificial atoms, are created by tightly confining electrons, and thereby quantizing their energies. They are important components in the emerging fields of nanotechnology where their potential uses vary from dyes to quantum computing qubits. Interesting properties to investigate are e.g. READ MORE