Erlangen 2018 – wissenschaftliches Programm
P 4.3: Vortrag
Montag, 5. März 2018, 14:45–15:00, KI 1.174
Optical analysis of nanosecond-pulsed plasmas generated in liquids — •Katharina Grosse, Julian Held, Marc Böke, and Achim von Keudell — Exprimental Physics 2, Ruhr-University Bochum, Germany
Plasmas generated inside liquids have aroused interest over the last years particularly in the field of plasma medicine. The reactive species created in such an environment can modify surfaces which are in direct contact with the treated liquid. The physics of these plasmas and the interaction of the particles created inside the liquid with biological and metallic surfaces is not fully investigated. The analysed plasma is generated by a high-voltage nanosecond pulser creating 10 ns pulses with varying amplitudes of 14-26 kV and a pulsing frequency of 1 Hz. The dynamics of the discharges are monitored with shadowgraphy imaging and the created species with optical emission spectroscopy. Four distinct phases of the plasma development can be identified: ignition and plasma phase (1), generation of a shock wave (2), formation of a gas bubble (3) and separation of the bubble from the high-voltage electrode (4). The shock wave velocity in phase (2) was estimated to approximately 3.3 km/s for the different applied voltages.