Sökning: "quantum thermodynamics"

Visar resultat 1 - 5 av 68 avhandlingar innehållade orden quantum thermodynamics.

  1. 1. Quantum-Dot Heat Engines

    Författare :Martin Josefsson; NanoLund: Centre for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; quantum dot; heat engine; thermoelectric; quantum thermodynamics; quantum transport; Fysicumarkivet A:2020:Josefsson;

    Sammanfattning : This thesis explores the possibilities of using quantum dots (QDs) in nanoscale energy har- vesters converting heat into electrical energy, i.e. heat engines. From a theory perspective, these possibilities have been investigated for almost two decades, and interest in them seem to continuously increase over time. LÄS MER

  2. 2. A General Formalism for Continuous Feedback Control in Quantum Systems

    Författare :Björn Annby-Andersson; NanoLund: Centre for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; quantum measurements; quantum control; stochastic thermodynamics; information thermodynamics; full count- ing statistics; open quantum systems; Quantum measurements; Quantum control; Stochastic thermodynamics; Information thermodynamics; Full counting statistics; Open quantum systems;

    Sammanfattning : This thesis devolops a general formalism for continuous feedback control in quantum systems. The main result is a quantum Fokker-Planck master equation describing the joint dynamics of a quantum system and a detector with finite bandwidth. For a fast detector, this equation can be reduced to a Markovian master equation for the system dynamics. LÄS MER

  3. 3. Resonant Tunneling in Laterally Confined Quantum Structures

    Författare :Boel Gustafson; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; gravitation; relativity; quantum mechanics; classical mechanics; Mathematical and general theoretical physics; Fysik; Physics; High peak-to-valley ratio; Lateral confinement; Quantum dots; Resonant tunneling; Self-assembled quantum dots; Schottky depletion; Buried metal gate; Electron transport; Magnetic-field dependence; Energy level width; Tunneling transistors; Mode coupling; statistical physics; thermodynamics; Matematisk och allmän teoretisk fysik; klassisk mekanik; kvantmekanik; relativitet; statistisk fysik; termodynamik; Technological sciences; Teknik; Fysicumarkivet A:2001:Gustafson;

    Sammanfattning : In the thesis, three-dimensionally confined resonant tunneling structures were studied experimentally. Two approaches were used for obtaining quantum confinement: gate-defined lateral constriction of double barrier structures, and epitaxial growth of self-assembled quantum dots. LÄS MER

  4. 4. Quantum Chaos and Dissipation in Finite Fermi Systems

    Författare :Sergiy Radionov; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; statistical physics; gravitation; relativity; Mathematical and general theoretical physics; classical mechanics; quantum mechanics; Dissipation; Quantum Chaos; Collective motion; thermodynamics; Matematisk och allmän teoretisk fysik; klassisk mekanik; kvantmekanik; relativitet; statistisk fysik; termodynamik;

    Sammanfattning : We address the problem of the dissipative character of collective motion in finite Fermi systems. We study this problem from the point of view of chaotic features of the fermionic degrees of freedom of the many-body Fermi systems. LÄS MER

  5. 5. Gaps, Traps and Lattices - Correlations in Small Quantum Systems

    Författare :Magnus Borgh; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetiska och optiska ; egenskaper elektriska; Cold atoms; Quantum dots; Optical lattices; classical mechanics; Mathematical and general theoretical physics; Exact diagonalization; Density Functional Theory; Vortices; relativity; quantum mechanics; termodynamik; statistisk fysik; relativitet; kvantmekanik; klassisk mekanik; Matematisk och allmän teoretisk fysik; thermodynamics; statistical physics; Condensed matter:electronic structure; gravitation; supraledare; magnetisk resonans; electrical; magnetic and optical properties; supraconductors; magnetic resonance; relaxation; spectroscopy; Kondenserade materiens egenskaper:elektronstruktur; spektroskopi; Fysicumarkivet A:2007:Borgh;

    Sammanfattning : This dissertation investigates properties of two-dimensional many-body systems. Studies are performed using the Spin-Density Functional Theory with the Local Spin-Density Approximation, and numerical exact diagonalization. LÄS MER