Sökning: "Quantum mechanics"

Visar resultat 6 - 10 av 188 avhandlingar innehållade orden Quantum mechanics.

  1. 6. Exploring the Set of Quantum States

    Författare :Åsa Ericsson; Ingemar Bengtsson; Christopher Fuchs; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum mechanics; quantum states; density matrices; quantum information; geometry; Physics; Fysik; Theoretical Physics; teoretisk fysik;

    Sammanfattning : Quantum mechanical properties of finite dimensional quantum systems are used within the field of quantum information. In this thesis the set of states (density matrices) for such systems is studied and described, largely in geometrical terms. LÄS MER

  3. 7. 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

  4. 8. Microwave Gaussian quantum metrology

    Författare :Robert Jonsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum Fisher Information; Bosonic channel; Quantum Sensing; Gaussian; Quantum Radar;

    Sammanfattning : With increasingly sensitive measurements being made possible by technological development, there arises situations where the effects of quantum mechanics have to be taken into account. While quantum mechanics tells us that there are fundamental limits of measurement sensitivity, it also gives us the tools to constructively push the same limits for experimental systems. LÄS MER

  5. 9. 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

  7. 10. Quantum technologies for secure communications

    Författare :Junior Ricardo Gonzales Ureta; Ana Predojević; Marcus Huber; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum technologies; quantum information; quantum optics; Physics; fysik;

    Sammanfattning : Quantum technologies promise to revolutionize a variety of fields such as metrology, cryptography or computing, among others. The resources that quantum mechanics offers allow us to design faster optimization algorithms, to improve security in communications, and to measure quantities beyond the grasp of current technology. LÄS MER