Gegenstand dieser Diplomarbeit ist die Untersuchung der Dynamik in dünnen Polymerfilmen anhand von einzelnen Molekülen. Zu diesem Zweck wurden dünne Filme (kleiner 100nm) hergestellt und mittels Einzelmoleküldetektion und zeitaufgelöster Einzelphotonenzählung analysiert, was eine orts- und zeitaufgelöste Untersuchung einzelner Farbstoffmoleküle ermöglicht. Ziel war es, festzustellen ob, und auf welchem Weg, die Dynamik der Umgebung in Fluktuationen der Fluoreszenzlebensdauer einzelner Moleküle sichtbar wird. Neben der Evaluierung der Untersuchungsmethoden wurden in dieser Arbeit zwei Arten von Sensormolekülen - DiD und Malachit Grün - näher untersucht. / The subject of this diploma thesis is the analysis of dynamics in thin polymer films using single molecules. Thin polymer films (less than 100nm) were produced and analysed by Single Molecule Detection (SMD) and Time Correlated Single Photon Counting (TCSPC). This allows a spatial and time resolved investigation of the single dye molecule. The aim was to ascertain if, and in which way, the dynamics of the environment are reflected by fluctuations of the fluorescence lifetime of the single molecule. In addition to evaluating the investigation methods two kinds of molecules - DiD and Malachite Green - were also analysed.

Nichtlineare Verzerrungen von Rasterkraftmikroskopie (engl.: scanning probe microscopy, Abk.: SPM) Bildern beeinträchtigen die Qualität von Nanotomographiebildern und SPM Bildsequenzen. In dieser Arbeit wird ein neues, nichtlineares Registrierungsverfahren vorgestellt, das auf einem für medizinische Anwendungen entwickelten Algorithmus aufbaut und diesen für die Behandlung von SPM Daten erweitert. Die nichtlineare Registrierung ermöglicht es, verschiedene nanostrukturierte Materialen über große Bereiche (1 µm x 1 µm) mit einer Auflösung von 10 nm abzubilden. Dies erlaubt eine wesentlich detailliertere quantitative Analyse der Daten. Hierfür wurde eine neue Datenreduktions- und Visualisierungsmethode für Mikrodomänennetzwerke von Blockcopolymeren eingeführt. Zwei- und dreidimensionale Mikrodomänenstrukturen werden zu ihrem Skelett reduziert, Verzweigungspunkte farblich codiert und der entstandene Graph visualisiert. Die Anzahl verschiedener Skelettverzweigungen lässt sich über die Zeit verfolgen. Die Methode wurde mit lokalen Minkowskimaßen der ursprünglichen Graustufenbilder verglichen. Sie liefert morphologische und geometrische Informationen auf unterschiedlichen Längenskalen.

We investigate systems with a mixed phase space, where regular and chaotic dynamics coexist. Classically, regions with regular motion, the regular islands, are dynamically not connected to regions with chaotic motion, the chaotic sea. Typically, this is also reflected in the quantum properties, where eigenstates either concentrate on the regular or the chaotic regions. However, it was shown that quantum mechanically, due to the tunneling process, a coupling is induced and flooding of regular islands may occur. This happens when the Heisenberg time, the time needed to resolve the discrete spectrum, is larger than the tunneling time from the regular region to the chaotic sea. In this case the regular eigenstates disappear. We study this effect by the time evolution of wave packets initially started in the chaotic sea and find increasing probability in the regular island. Using random matrix models a quantitative prediction is derived. We find excellent agreement with numerical data obtained for quantum maps and billiards systems. For open systems we investigate the phenomenon of flooding and disappearance of regular states, where the escape time occurs as an additional time scale. We discuss the reappearance of regular states in the case of strongly opened systems. This is demonstrated numerically for quantum maps and experimentally for a mushroom shaped microwave resonator. The reappearance of regular states is explained qualitatively by a matrix model. / Untersucht werden Systeme mit gemischtem Phasenraum, in denen sowohl reguläre als auch chaotische Dynamik auftritt. In der klassischen Mechanik sind Gebiete regulärer Bewegung, die sogenannten regulären Inseln, dynamisch nicht mit den Gebieten chaotischer Bewegung, der chaotischen See, verbunden. Dieses Verhalten spiegelt sich typischerweise auch in den quantenmechanischen Eigenschaften wider, so dass Eigenfunktionen entweder auf chaotischen oder regulären Gebieten konzentriert sind. Es wurde jedoch gezeigt, dass aufgrund des Tunneleffektes eine Kopplung auftritt und reguläre Inseln geflutet werden können. Dies geschieht wenn die Heisenbergzeit, das heißt die Zeit die das System benötigt, um das diskrete Spektrum aufzulösen, größer als die Tunnelzeit vom Regulären ins Chaotische ist, wobei reguläre Eigenzustände verschwinden. Dieser Effekt wird über eine Zeitentwicklung von Wellenpaketen, die in der chaotischen See gestartet werden, untersucht. Es kommt zu einer ansteigenden Wahrscheinlichkeit in der regulären Insel. Mithilfe von Zufallsmatrixmodellen wird eine quantitative Vorhersage abgeleitet, welche die numerischen Daten von Quantenabbildungen und Billardsystemen hervorragend beschreibt. Der Effekt des Flutens und das Verschwinden regulärer Zustände wird ebenfalls mit offenen Systemen untersucht. Hier tritt die Fluchtzeit als zusätzliche Zeitskala auf. Das Wiederkehren regulärer Zustände im Falle stark geöffneter Systeme wird qualitativ mithilfe eines Matrixmodells erklärt und numerisch für Quantenabbildungen sowie experimentell für einen pilzförmigen Mikrowellenresonator belegt.

All fields of physics - be it nuclear, atomic and molecular, solid state, or optical - offer examples of systems which are strongly influenced by the environment of the actual system under investigation. The scope of what is called "the environment" may vary, i.e., how far from the system of interest an interaction between the two does persist. Typically, however, it is much larger than the open system itself. Hence, a fully quantum mechanical treatment of the combined system without approximations and without limitations of the type of system is currently out of reach. With the single assumption of the environment to consist of an internally thermalized set of infinitely many harmonic oscillators, the seminal work of Stockburger and Grabert [Chem. Phys., 268:249-256, 2001] introduced an open system description that captures the environmental influence by means of a stochastic driving of the reduced system. The resulting stochastic Liouville-von Neumann equation describes the full non-Markovian dynamics without explicit memory but instead accounts for it implicitly through the correlations of the complex-valued noise forces. The present thesis provides a first application of the Stockburger-Grabert stochastic Liouville-von Neumann equation to the computation of the dynamics of anharmonic, continuous open systems. In particular, it is demonstrated that trajectory based propagators allow for the construction of a numerically stable propagation scheme. With this approach it becomes possible to achieve the tremendous increase of the noise sample count necessary to stochastically converge the results when investigating such systems with continuous variables. After a test against available analytic results for the dissipative harmonic oscillator, the approach is subsequently applied to the analysis of two different realistic, physical systems. As a first example, the dynamics of a dissipative molecular oscillator is investigated. Long time propagation - until thermalization is reached - is shown to be possible with the presented approach. The properties of the thermalized density are determined and they are ascertained to be independent of the system's initial state. Furthermore, the dependence on the bath's temperature and coupling strength is analyzed and it is demonstrated how a change of the bath parameters can be used to tune the system from the dissociative to the bound regime. A second investigation is conducted for a dissipative tunneling scenario in which a wave packet impinges on a barrier. The dependence of the transmission probability on the initial state's kinetic energy as well as the bath's temperature and coupling strength is computed. For both systems, a comparison with the high-temperature Markovian quantum Brownian limit is performed. The importance of a full non-Markovian treatment is demonstrated as deviations are shown to exist between the two descriptions both in the low temperature cases where they are expected and in some of the high temperature cases where their appearance might not be anticipated as easily.

No description available.

No description available.

In processing and data storage mainly ferromagnetic (FM) materials are being used. Approaching physical limits, new concepts have to be found for faster, smaller switches, for higher data densities and more energy efficiency. Some of the discussed new concepts involve the material classes of correlated oxides and materials with antiferromagnetic coupling. Their applicability depends critically on their switching behavior, i.e., how fast and how energy efficient material properties can be manipulated. This thesis presents investigations of ultrafast non-equilibrium phase transitions on such new materials. In transition metal oxides (TMOs) the coupling of different degrees of freedom and resulting low energy excitation spectrum often result in spectacular changes of macroscopic properties (colossal magneto resistance, superconductivity, metal-to-insulator transitions) often accompanied by nanoscale order of spins, charges, orbital occupation and by lattice distortions, which make these material attractive. Magnetite served as a prototype for functional TMOs showing a metal-to-insulator-transition (MIT) at T = 123 K. By probing the charge and orbital order as well as the structure after an optical excitation we found that the electronic order and the structural distortion, characteristics of the insulating phase in thermal equilibrium, are destroyed within the experimental resolution of 300 fs. The MIT itself occurs on a 1.5 ps timescale. It shows that MITs in functional materials are several thousand times faster than switching processes in semiconductors. Recently ferrimagnetic and antiferromagnetic (AFM) materials have become interesting. It was shown in ferrimagnetic GdFeCo, that the transfer of angular momentum between two opposed FM subsystems with different time constants leads to a switching of the magnetization after laser pulse excitation. In addition it was theoretically predicted that demagnetization dynamics in AFM should occur faster than in FM materials as no net angular momentum has to be transferred out of the spin system. We investigated two different AFM materials in order to learn more about their ultrafast dynamics. In Ho, a metallic AFM below T ≈ 130 K, we found that the AFM Ho can not only be faster but also ten times more energy efficiently destroyed as order in FM comparable metals. In EuTe, an AFM semiconductor below T ≈ 10 K, we compared the loss of magnetization and laser-induced structural distortion in one and the same experiment. Our experiment shows that they are effectively disentangled. An exception is an ultrafast release of lattice dynamics, which we assign to the release of magnetostriction. The results presented here were obtained with time-resolved resonant soft x-ray diffraction at the Femtoslicing source of the Helmholtz-Zentrum Berlin and at the free-electron laser in Stanford (LCLS). In addition the development and setup of a new UHV-diffractometer for these experiments will be reported. / In der Datenspeichertechnologie werden bisher hauptsächlich ferromagnetische Materialien eingesetzt. Da mit diesen aber physikalische Grenzen erreicht werden, werden neue Konzepte gesucht, um schnellere und kleinere Schalter, größere Datendichten und eine höherere Energieeffizienz zu erzeugen. Unter den diskutierten Materialklassen finden sich komplexen Übergangsmetalloxide und Materialien mit antiferromagnetischer Kopplung. Die Anwendbarkeit solcher Materialien hängt stark davon ab, wie schnell sich deren Eigenschaften verändern lassen und wieviel Energie dafür eingesetzt werden muss. Die vorliegende Arbeit beschäftigt sich mit ultraschnellen, Nicht-Gleichgewicht-Phasenübergängen genau in solchen Materialien. In Übergangsmetalloxiden führt die enge Kopplung zwischen den unterschiedlichen Freiheitsgraden zu einem effektiven niederenergetischen Anregungsspektrum. Diese Anregungen sind oft verknüpft mit spektakulären makroskopischen Eigenschaften, wie z.B. dem kolossalen Magnetowiderstand, Hochtemperatur-Supraleitung, Metall- Isolator-Übergang, die oft von nanoskaliger Ordnung von Spins, Ladungen, orbitaler Besetzung sowie Gitterverzerrungen begleitet sind. Dadurch werden diese Materialien interessant für Anwendbarkeit. Magnetit, ein Prototyp eines solchen funktionalen Materials zeigt einen Metall-Isolator-Übergang bei T = 123 K. Untersucht man die Ladungs- und orbitale Ordnung sowie die Struktur nach einer optischen Anregung, so findet man, dass die elektronische Struktur und Gitterverzerrung, die kennzeichnend für die Tieftemperaturphase sind, innerhalb der Zeitauflösung des Experiments von 300 fs zerstört wird. Der eigentliche Metall-Isolator-Übergang zeigt sich erst nach 1.5 ps. Die Ergebnisse zeigen, dass MITs in funktionalen Materialien bis zu tausend Mal schneller geschaltet werden können als in vorhandenen Halbleiter-Schaltern. Seit kurzem rücken auch ferrimagnetische und antiferromagnetische Materialen in den Fokus des Interesses. Es wurde im Ferrimagnet GdFeCo gezeigt, dass der Transfer von Drehimpuls zwischen zwei entgegengesetzten Subsystemen mit unterschiedlichen Zeitkonstanten zu einem Umschalten der Magnetisierung führt. Zudem wurde vorhergesagt, dass Demagnetisierungsdynamiken in antiferromagnetischen Materialien schneller ablaufen soll als in ferromagnetischen, da kein Drehimpuls aus dem Spinsystem abgeführt werden muss. Damit wir mehr über antiferromagnetische Dynamik erfahren haben wir zwei unterschiedliche Antiferromagneten untersucht, um sie mit den bekannten FM zu vergleichen. Im metallischen AFM Holmium fanden wir, dass die magnetische Ordnung schneller und zehnmal energieeffizienter zerstört werden kann als in vergleichbaren FM Metallen. In Europium-Tellurid, einem antiferromagnetischem Halbleiter, haben wir den Zerfall der magnetischen Ordnung im Hinblick auf Wechselwirkungen mit der Struktur untersucht. Wir fanden auf kurzen Zeitskalen eine eher entkoppelte Dynamik. Eine Ausnahme ist ein schneller Beitrag zur Gitterdynamik, den wir mit dem Wegfall von Magnetostriktion erklären. Die hier gezeigten Ergebnisse wurden mit Hilfe zeitaufgelöster resonanter weicher Röntgenbeugung an der Femtoslicing Strahlungsquelle des Helmholtz-Zentrums Berlin und am freien Elektronenlaser LCLS gemessen. Zusätzlich wird über die Entwicklung und den Bau eines UHV-Diffraktometers für diese Experimente berichtet.

Zugl.: Darmstadt, Techn. Universiẗat, Diss.

The resource demand on embedded devices is constantly growing. This is caused by the sheer explosion of software based functions in embedded systems, that are growing far faster than the resources of the single-core and multi-core embedded processors. As one of the limitation is the computing power of the processors we need to explore ways to use this resource more efficiently. We identified that during the run-time of the embedded devices the resource demand of the software functions is permanently changing dependent on the device situation. To enable an embedded device to take advantage of this dynamic resource demand, the allocation of the software functions to the processor must be handled by a scheduler that is able to evaluate the resource demand of the software functions in relation to the device situation. This marks a change in embedded devices from static defined software systems to dynamic software systems. Above that we can increase the efficiency even further by extending the approach from a single device to a distributed or networked system (many-core system). However, existing approaches to deal with dynamic resource allocation are focused on individual devices and leave the optimization potential of manycore systems untouched. Our concept will extend the existing Hierarchical Asynchronous Multi-Core Scheduler (HAMS) concept for individual devices to many-core systems. This extension introduces a dynamic situation aware scheduler for many-core systems which take the current workload of all devices and the system-situation into account. With our approach, the resource efficiency of an embedded many-core system can be increased. The following paper will explain the architecture and the expected results of our concept.

Flood risks in urban settlements are often determined based upon hydrological and hydrodynamic design events and the existing building stock. After a flood event, a high discrepancy between the assessed risk, the observed flow conditions and resulting loss and damage in flood prone areas is mostly found. This illustrates that flood risks are subject to high spatial and temporal dynamics. Hence, the assessment of the dynamics of flood risks involves considerable variability (variations in the mean state) and change (medium-/long-term trends). In addition, uncertainties play a significant role. Current risk assessment approaches do not sufficiently represent all processes relevant for the dynamics and uncertainties of flood risk generation. The aim of the thesis is a comprehensive research on the dynamics and uncertainties of fluvial flood risks due to variability and change. It pursues the objective to generate risk curves describing the dynamics (variability and change) and their epistemic uncertainties. To achieve this three research questions are answered. The first research question (RQ1) “What are the influences of the dynamics of flood risks?” identifies (i) major processes involved in flood risk generation, (ii) factors of these processes prone to variability and change, and (iii) drivers triggering the factor’s alteration. The second research question (RQ2) “What is an appropriate way to simulate and analyse the dynamics of flood risks?” concentrates on modules and tools for simulations of the entire flood risk system, the impacts of the drivers, and uncertainties. The answer of RQ2 focuses on climate change as one (group of) driver(s) of dynamics (change) and simulates the current state and future scenarios. The third research question (RQ3) ”What are the flood risk dynamics in a specific catchment?” is determined quantitatively resulting in risk curves with their uncertainty bounds. To investigate the dynamics and uncertainties of flood risks a three-tiered framework is designed including (1) a conceptual, (2) a methodological and (3) a technological framework. The Conceptual Framework (CF) is assigned to RQ1 focusing on the main drivers of the dynamics by conceptualisation of different subsystems for the assessment of flood risks. The Methodological Framework (MF) is used to answer RQ2 providing an appropriate way to simulate and analyse the dynamics of flood risks by methodical operationalisation of the subsystems through modules. It focuses on climate change considering simulations of future scenarios and various sources of uncertainties. The Technological Framework (TF) describes how different modules and methods are combined to implement the MF by technical realisation of the sequence of modules. An investigation area is selected for empirical testing of the three-tiered framework. Four modules are developed and tested by a comprehensive multi-model chain representing the flood risk system of the Mulde River catchment and the municipality of Bennewitz. The first module Climate Data Ensemble applies two climate data ensembles: WEREX V and COSMO-CLM accounting for climate variability as well as future change by climate scenarios and uncertainties due to climate models and realisation runs. The second module Hydrologic Modelling uses two models: HBV and WaSiM-ETH optimised by AMALGAM to generate flood events. This module addresses model and parameter uncertainty. The third module Hydrodynamic Modelling applies HEC-RAS and LISFLOOD-FP to derive inundation areas and to account for model uncertainty. The fourth module Damage Modelling combines construction and inventory damage. Risk curves with their bandwidth due dynamics and uncertainties are generated. The analysis of the dynamics and uncertainties is carried out by means of the ANOVA approach allowing for a quantification of the impacts due to the selected climate scenario, climate model, realisation, and hydrological parameter set. A large contribution of climate models and the rather small influence of hydrological parametrisation on rare flood events are detected. A wide range in the risk curves illustrates the influence of climate scenarios, climate models, and hydrologic parametrisations on monetary damages. The large number of high resolution, continuous long-term model runs as well as model coupling for the flood risk system, makes high performance computing (HPC) and big data assessment essential.:1 Introduction 1.1 Background 1.2 Problem Statement 1.3 Aim, Objective and Research Questions 1.4 Research Strategy and Outline 2 State of the Art 2.1 Flood Risks and Flood Risk Systems 2.2 Dynamics of Flood Risk Systems 2.3 Assessment of Flood Risk Considering Change and Uncertainty 3 Three-tiered Framework for the Assessment of the Dynamics of Flood Risks 3.1 Conceptual Framework 3.1.1 Major Processes of Flood Risk Generation 3.1.1.1 Atmospheric Processes 3.1.1.2 Hydrologic Processes 3.1.1.3 Hydrodynamic Processes 3.1.1.4 Loss and Damage Processes 3.1.1.5 Flood Risks 3.1.2 Factors Prone to Variability and Change 3.1.3 Identification of Drivers and Dynamics 3.2 Methodological Framework 3.2.1 Simulation of Flood Risks 3.2.1.1 Atmospheric Processes – Climate Data Ensemble Module 3.2.1.2 Hydrologic Processes – Hydrological Modelling Module 3.2.1.3 Hydrodynamic Processes – Hydrodynamic Modelling Module 3.2.1.4 Loss and Damage Processes – Damage Modelling Module 3.2.1.5 Flood Risks 3.2.2 Dynamics of Flood Risks Caused by Climate Change as Driver and Uncertainties 3.3 Technological Framework 3.3.1 Software Components 3.3.1.1 Climate Data Ensemble Module 3.3.1.2 Hydrological Modelling Module 3.3.1.3 Hydrodynamic Modelling Module 3.3.1.4 Damage Modelling Module 3.3.1.5 Flood Risks Investigated by Visual Analytics 3.3.2 Development Protocols 4 Implementation of the Framework as Methodology and Empirical Testing 4.1 Flood Risk System of the Mulde River and the Municipality of Bennewitz 4.2 Methodology Testing for the Mulde River and the Municipality of Bennewitz 4.2.1 Climate Data Ensemble Module 4.2.1.1 Module Implementation 4.2.1.2 Results for the Reference Period 4.2.1.3 Results for Future Projections 4.2.2 Hydrologic Modelling Module 4.2.2.1 Module Implementation 4.2.2.2 Results for the Reference Period 4.2.2.3 Results for Future Projections 4.2.3 Hydrodynamic Modelling Module 4.2.3.1 Module Implementation 4.2.3.2 Results for the Reference Period 4.2.3.3 Results for Future Projections 4.2.4 Damage Modelling Module 4.2.4.1 Module Implementation 4.2.4.2 Results for Future Projections 4.3 Dynamics of Flood Risks Resulting in Flood Risk Curves and Uncertainty Quantification 5 Discussion 5.1 Discussion of the Three-tiered Framework 5.2 Discussion of the Implementation of the Framework as Methodology and Empirical Testing 5.2.1 Climate Data Ensemble Module 5.2.2 Hydrologic Modelling Module 5.2.3 Hydrodynamic Modelling Module 5.2.4 Damage Modelling Module 5.2.5 Dynamics of Flood Risks Resulting in Flood Risk Curves and Uncertainty Quantification 6 Conclusions and Outlook 6.1 Conclusions 6.2 Outlook References A Appendix Basic Information B Appendix Results B.1 Appendix Results Climate Data Ensemble Module B.2 Appendix Results Hydrologic Modelling Module B.3 Appendix Results Hydrodynamic Modelling Module B.4 Appendix Results Damage Modelling Module B.5 Appendix Results Dynamics and Uncertainties of Flood Risks