Impulsive interband excitation with femtosecond near-infrared pulses establishes a plasma response in intrinsic germanium structures fabricated on a silicon substrate. This direct approach activates the plasmonic resonance of the Ge structures and enables their use as optical antennas up to the mid-infrared spectral range. The optical switching lasts for hundreds of picoseconds until charge recombination redshifts the plasma frequency. The full behavior of the structures is modeled by the electrodynamic response established by an electron-hole plasma in a regular array of antennas.

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A new method for the characterization of coherent laser beams is proposed. It is based on the non-iterative solution of the transport-of-intensity-equation. The phase to recover is decomposed into paraxial properties of laser beams and a set of lateral shifted radial basis functions, which allows for the derivation of a direct solution of the phase by a least-squares fit without the need of an initial guess. The method is tested with synthetic data to deduce an accuracy metric. Additionally, two real laser beams are characterized. Including the real light source in terms of the reconstructed field allows for a more holistic simulation of optical systems.

The use of higher laser powers in laser cutting of CFRP results in both an increase of productivity and in a growth of the heat affected zone at the cut edge. This thermal damage was related to a loss of the static strength due to the reduce load bearing cross section in various studies. In contrast, the thermal damage caused an increase of the average number of load cycles and to a significant reduction of the deviation among the repetitions of each parameter during dynamic open hole tensile testing in recent studies. To explain this positive influence of laser cutting on the fatigue behaviour of CFRP, an analytical model of the load concentration in a plate with a circular notch could be adapted and modified. The orthotropic property of the material is considered in the model. The static strength of thermally treated CFRP was determined in experiments and applied to the model. By inserting the measured temperature-dependent values of the Young´s modulus, the critical tension at the notch could be determined related to the dimensions of the heat affected zone.

The requirements needing to be met by handling technologies and factory automation in semiconductor fabrication and microsystem s technology are rising relentlessly. Fragile, surface -sensitive and thinned substrates call for new, innovative approaches in order to tackle numerous material handling tasks. Therefore a new upcoming handling technology based on the ultrasound -air-film-technology and its applications for non -contact handling in PV -Thin-Film and microassembly are presented in this paper.