Open Microwave Systems: Tunneling, Correlations and Time-Dependent Variations

In this thesis three possibilities of external influences in wave mechanical systems are analyzed. In all three cases I used microwave devices to study quantum mechanical systems. The first analyzed property is the decay rate from states in so-called regular islands in a billiard system to the chaotic sea. Afterwards I characterize the influence of open decay channels in transport through chaotic wave systems. The last topic is the introduction of a time-dependently changed microwave device. In the first chapter the decay of a wave function from one classically isolated phase space region to another is analyzed. The main interest lies on the influence of additional states corresponding to the same original phase space region. I will show that these states can lead to an enhancement of the decay rate. The decay rates are measured via an indirect absorption process, leading to an increase of the corresponding resonance widths. Alternatively to mode depending width properties, which were typically analyzed in numerical calculations, a parameter depending variation of the system is introduced to verify the demanded effect. The experimental and numerical determination of channel correlations are the subject of the second chapter. After defining the correlation function, an experimental demonstration is presented. The results of the experiment and the describing numerics show that the correlation functions are important for the characterization of universal conductance fluctuations. The last chapter deals with the realization of a periodically driven microwave system. The principal setup is a resonant circuit with a time-dependent capacity. The properties of the setup, e.g. sideband structures for different driving signals, are analyzed experimentally, theoretically and numerically. This is the first step to create a system where a huge subset of resonances is changed. The fulfilled description of the single resonance system is presented and the next steps to realizations of time-dependent driven wave mechanical systems are sketched