Ultrafast nonlinear effects in one-dimensional photonic crystals

This thesis deals with the temporal dynamics of light interacting with a special class of nano-structures: so-called photonic crystals (PCs). The focus of these investigations is nonlinear phenomena on a sub-picosecond time scale. PCs are solid-state nano-structures with a spatially periodic dielectric function. They influence propagating light in an analogous manner to that of electronic motion in a periodic lattice potential of a semiconductor or metal. These structures are said to be one-, two-, or three-dimensional, depending on their spatial periodicity. For this thesis, two different types of one-dimensional PCs have been studied: semiconductor multiple-quantum-well (MQW) Bragg structures, which are resonant PCs, and metal-dielectric PCs. For both material systems, the fundamental light-matter interaction processes, as well as potential applications, are discussed. The properties of MQW Bragg structures have been investigated by phaseresolved pulse propagation measurements. Several light-matter interaction regimes, ranging from linear excitation to high-intensity phenomena such as self-phase modulation, have been studied in great detail. It has been possible to make a clear distinction between the bulk properties and the influence of the quantum wells. The results constitute a considerable contribution to the fundamental understanding of semiconductor nano-structures. The experiments performed on one-dimensional metal-dielectric PCs are pioneering work in that they have studied the temporal dynamics in such structures for the very first time. These structures are especially interesting for application in ultrafast optical devices. Several predictions about their transmission dynamics could be tested in the measurements presented here. Essentially, two effects on different time and magnitude scales where observed, and a significantly different behavior as compared to single nano-scale metal layers could be identified.