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31	Investigations of transport phenomena and dynamical relaxation in closed quantum systems Khodja, Abdellah 17 March 2015 (has links) The first part of the present Phd thesis is devoted to transport investigations in disordered quantum systems. We aim at quantitatively determining transport parameters like conductivity, mean free path, etc., for simple models of spatially disordered and/or percolated quantum systems in the limit of high temperatures and low fillings using linear response theory. We find the transport behavior for some models to be in accord with a Boltzmann equation, i.e., long mean free paths, exponentially decaying currents although there are no band-structures to start from, while this does not apply to other models even though they are also almost completely delocalized. The second part of the present PhD thesis addresses the issue of initial state independence (ISI) in closed quantum system. The relevance of the eigenstate thermalization hypothesis (ETH) for the emergence of ISI equilibration is to some extent addressed. To this end, we investigate the Heisenberg spin-ladder and check the validity of the ETH for the energy difference operator by examining the scaling behavior of the corresponding ETH-fluctuations, which we compute using an innovative numerical method based on typicality related arguments. While, the ETH turns out to hold for the generic non-integrable models and may therefore serve as the key mechanism for ISI for this cases, it does not hold for the integrable Heisenberg-chain. However, close analysis on the dynamic of substantially out-of-equilibrium initial states indicates the occurrence of ISI equillibration in the thermodynamic limit regardless of whether the ETH is violated. Thus, we introduce a new parameter $v$, which we propose as an alternative of the ETH to indicate ISI equillibration in cases, in which the ETH does not strictly apply. transport coefficients Boltzmann equation eigenstate thermalization hypothesis 33.23 - Quantenphysik 33.10 - Theoretische Physik: Allgemeines 33.66 - Amorpher Zustand, Gläser ddc:530
32	Relaxationen in komplexen Fluiden / Relaxations of complex fluids Schwabe, Moritz 02 November 2010 (has links) No description available. 530 Physik Physics Metallisches Glas Relaxationsprozesse Glasübergangstemperatur potentielle Energielandschaft Spannungsabhängigkeit Aktivierungsvolumen Block-Copolymere Chemical Confinement Wasserstoffbrücken metallic glass relaxation processes glass transition temperature potential energy landscape stress dependence activation volume block-copolymers chemical confinement hydrogen bonds 33.66 Amorpher Zustand Gläser RVI 000 Nichtkristalline Festkörper
33	Low Temperature Phase of the m-component Spin Glass / Die Tieftemperaturphase des m-Komponenten Spinglases Braun, Axel 29 June 2011 (has links) No description available. 530 Physik Physics Spinglas große Komponentenanzahl m Bethe-Gitter Cavitymethode Replikasymmetriebrechung Sample-to-sample Fluktuationen Universalitätsklassen Spin glass large-m Bethe lattice Cavity method Generalized Bose-Einstein condensation Replica symmetry breaking Sample-to-sample fluctuations Universality classes 33.25 Thermodynamik statistische Physik 33.66 Amorpher Zustand Gläser 33.75 Magnetische Materialien RVI 000 Nichtkristalline Festkörper RDI 700 Statistische Physik Quantenstatistik
34	Mechanische Eigenschaften kristallin-amorpher Schichtpakete / Mechanical properties of crystalline-amorphous multilayers Knorr, Inga 13 December 2012 (has links) No description available. 530 Physik Physik (PPN621336750) Metalle {Physik} (PPN621341347) Physics Mechanische Eigenschaften dünne Schichten Schichtpakete Nanokomposit Festigkeit Duktilität Verformungsmechanismen Nanoindentierung Mikrodruckversuche mechanical properties thin films multilayers nanocomposite strength ductility deformation mechanisms nanoindentation microcompression 33.00 Physik: Allgemeines 33.68 Oberflächen Dünne Schichten Grenzflächen 33.62 Mechanische Eigenschaften akustische Eigenschaften thermische Eigenschaften 33.66 Amorpher Zustand Gläser
35	Short range ordering and microstructure property relationship in amorphous alloys / Nahordnung und Mikrostruktur-Eigenschaftsbeziehungen in amorphen Legierungen Shariq, Ahmed 09 January 2007 (has links) No description available. 530 Physik Mathematics and Computer Science metallische Gläser amorphe Legierungen weich magnetische Eigenschaften Komposite Mikrostruktur Nahordnung radiale Verteilungsfunktion next neighbourhood evaluation Modul Atom sonden Tomographie Transmissionselektronen Mikroskopie metallic glasses amorphous alloys soft ferromagnetic properties composites microstructure short range ordering radial distribution function next neighbourhood evaluation module atom probe tomography transmission electron microscopy 33.66 Amorpher Zustand Gläser 33.75 Magnetische Materialien 51.10 Metallphysik 33.05 Experimentalphysik

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