Sökning: "Quantum coherence"

Visar resultat 1 - 5 av 56 avhandlingar innehållade orden Quantum coherence.

  1. 1. Quantum Coherence for Light Harvesting

    Författare :David Palecek; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Coherent two-dimensional spectroscopy; Quantum coherence; Light harvesting; Photosynthetic reaction center; Energy transfer;

    Sammanfattning : Almost all life on Earth depends on the products of photosynthesis — the biochemical process whereby solar energy is stored as chemical-rich compounds. The energy of captured photons is transferred through a network of pigment-protein complexes towards the reaction center. LÄS MER

  2. 2. Quantum Coherence and Quantum-Vacuum Effects in Some Artificial Electromagnetic Media

    Författare :Jianqi Shen; Sailing He; Chris Phillips; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Quantum coherence; quantum vacuum; electromagnetically induced transparency; negative refractive index; artificial electromagnetic media; electric- and magnetic-dipole transitions; multilevel atomic vapors; transient evolution; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

    Sammanfattning : The author of this thesis concentrates his attention on quantum optical properties of some artificial electromagnetic media, such as quantum coherent atomic vapors (various multilevel electromagnetically induced transparency vapors) and negative refractive index materials, and suggests some possible ways to manipulate wave propagations inside the artificial electromagnetic materials based on quantum coherence and quantum vacuum effects. In Chapters 1 and 2, the author reviews the previous papers on quantum coherence as well as the relevant work such as electromagnetically induced transparency (EIT), atomic population trapping and their various applications. LÄS MER

  3. 3. Quantum Resources for Efficient Excitation Energy Transfer in Natural and Artificial Pigment-Protein Molecular Aggregates

    Författare :Charlotta Bengtson; Erik Sjöqvist; Susana Huelga; Uppsala universitet; []
    Nyckelord :Quantum coherence; quantum correlations; quantum nonlocality; open quantum systems; non-Markovian dynamics; Kemi med inriktning mot kvantkemi; Chemistry with specialization in Quantum Chemistry;

    Sammanfattning : Recently, long-lasting quantum effects in a number of photosynthetic complexes, which are pigment-protein molecular aggregates (PPMAs), were experimentally verified. These findings created an interest in trying to connect the known highly efficient excitation energy transfer (EET) in these systems to the existence of quantum effects such as quantum coherence and quantum correlations. LÄS MER

  4. 4. Quantum Coherence in the Single Cooper Pair Box

    Författare :Kevin Bladh; Chalmers University of Technology; []
    Nyckelord :coherent oscillations; single Cooper pair box; quantum coherence; radio frequency single electron transistor; cryogenic filters;

    Sammanfattning : This thesis presents measurements of quantum coherence in a single Cooper pair box, where quantum oscillations of charge between a reservoir and a small superconducting island have been observed. The single Cooper pair box (SCB) consists of a small metallic island which is connected to a reservoir via a tunnel junction. LÄS MER

  5. 5. The Single Cooper Pair Box - a Quantum-Mechanical Electronic Circuit

    Författare :David Gunnarsson; Chalmers University of Technology; []
    Nyckelord :quantum capacitance; quantum computing; single Cooper-pair box; SET; radio-frequency single-electron-transistor; macroscopic quantum coherence; Qubit;

    Sammanfattning : In this thesis the single Cooper pair box (SCB) is investigated with a radio frequency single electron transistor (RF-SET). The RF-SET is used as an electrometer to detect the charge of the SCB. The SCB can be regarded as a quantum two-level system and could therefore be a possible qubit. LÄS MER