Investigation of shock waves and fluid flows which are generated by short and ultrashort intense laser pulses within a small volume (lateral dimension less than 10 micron, mostly micro channels)

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Topic is the investigation of intense nano, pico and femtosecond laser pulse generated shock waves in gases or liquids (or in general in a fluid) within a small volume. The shock waves will be generated in fluids within micro channels (in the following micro channel should term very small channels and/or capillaries). Parameters of the fluid and changes of its state will be investigated in front of and behind the incident and reflected shock. In contrast to mini shock waves that are initiated by membrane bursts in larger scale pipes, the micro shock waves of the present project will be generated from a high power laser generated plasma, e.g. within a micro channel or directly in front of it. The investigations will be concentrated on: a) plasma formation and expansion, b) density and velocity within the region of generation and c) within the induction distance of the micro channel and finally d) in the region of stabilized plane shock waves. For the investigations various diagnostics with temporal resolution will be applied (laser differential interferometry, Moire diagnostics, LDA, PIV, etc.). In particular, with respect to the international community, micro shock waves generated by intense laser pulses comprise a new area of physics. The acquired results will built an important physical fundament for applications such as micro fluidics, nano technology, medical physics and many other interesting topics.