Sökning: "Quantum mechanical effects"

Visar resultat 16 - 20 av 58 avhandlingar innehållade orden Quantum mechanical effects.

  1. 16. Energy and Electron Transfer in Porphyrin-Based Donor--Bridge--Acceptor Systems

    Författare :Kristine Kilså; Chalmers University of Technology; []
    Nyckelord :electron transfer; electronic coupling; donor--bridge--acceptor systems; quantum mechanical calculations; enhanced intersystem crossing; ligand and solvent effects; bridge mediation; energy transfer; porphyrin;

    Sammanfattning : The photophysical properties of supramolecular donor--bridge--acceptor systems have been investigated by spectroscopic and quantum mechanical methods. The systems consist of porphyrin donor and acceptor moieties linked by bridging chromophores of varying excitation energy, and are shown to be geometrically well-defined in terms of length and rotational conformation. LÄS MER

  2. 17. Electronic and optical properties of conducting polymers from quantum mechanical computations

    Författare :Amina Mirsakiyeva; Anna Delin; Igor Zozoulenko; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES; density functional theory; DFT; Car-Parrinello molecular dynamics; CPMD; tigh-binding; poly 3; 4-ethylenedioxythiophene ; PEDOT; selenium; PEDOS; tellurium; PEDOTe; poly p-phenylene ; poly para-phenylene ; poly 1; 4-phenylene ; naphthobischalcogenadiazoles; Physics; Fysik;

    Sammanfattning :     Conductive polymers are also known as "organic metals" due to their semiconducting properties. They are found in a wide range of applications in the field of organic electronics. However, the growing number of experimental works is not widely supported with theoretical calculations. LÄS MER

  3. 18. Parity Effects in Single Charge Tunneling

    Författare :Magnus Gisselfält; Chalmers University of Technology; []
    Nyckelord :mesoscopic; single charge tunneling; photon-assisted tunneling; shot noise; SET transistor; parity effect; Andreev tunneling; Coulomb blockade;

    Sammanfattning : The subject of this thesis is single charge tunneling effects, especially parity effects, as they are manifested in quantum mechanical tunneling through a metallic island small enough to cause single electrons to block tunneling of other electrons due to Coulomb interaction. When the island is superconducting the ground state energy depends on the parity of the number of electrons on the island: outside of the condensate there will always be at least one electron contributing to the energy for an odd number of electrons and this will have observable consequences. LÄS MER

  4. 19. Fast-tunable resonators and quantum electrical circuits

    Författare :Martin Sandberg; Chalmers University of Technology; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; SEB; tunable; Sisyphus resistance; CPW; Resonator; SCB; qubit; circuit-QED; transmon; SQUID;

    Sammanfattning : In this thesis, measurements on superconducting electrical circuits that exhibit quantum mechanical effects are presented. Nonlinear superconducting circuits can be regarded as artificial atoms with energy spectra that can be engineered. The artificial atoms can be used as quantum bits for quantum computation. LÄS MER

  5. 20. Interaction between electronic and vibrational edge states in graphene

    Författare :Anton Vikström; Chalmers University of Technology; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; collective excitations; quantum acous- tics; quantum Hall effect; edge waves; graphene; solitons;

    Sammanfattning : A sheet of graphene in a magnetic field perpendicular to the sheet has electronic edge states with nonzero velocities. These edge states are localized to the edge of the sheet on the order of the magnetic length. LÄS MER