Target current: An appropriate parameter for characterizing the dynamics of laser-matter interaction

0508654 - ÚFP 2020 US eng C - Conference Paper (international conference)
Krása, J. - Klír, Daniel - Řezáč, Karel - Cikhardt, Jakub - Velyhan, A. - Pfeifer, M. - Dostál, Jan - Krůs, Miroslav - Dudžák, Roman - Buryšková, S. - Nassisi, V. - Delle Side, D.
Target current: An appropriate parameter for characterizing the dynamics of laser-matter interaction.
Proceedings of SPIE The International Society for Optical Engineering. Bellingham: SPIE, 2018, Roč. 11042 (2018), č. článku 110420X. ISBN 9781510621350. ISSN 0277-786X.
[22nd International Symposium on High Power Laser Systems and Applications. Frascati (IT), 09.10.2018-12.10.2018]
R&D Projects: GA MŠMT(CZ) LM2015083; GA MŠMT(CZ) CZ.02.1.01/0.0/0.0/16_013/0001552
Institutional support: RVO:61389021
Keywords : laser produced-plasma * phases of laser-produced plasma * plasma barrier * return target current
OECD category: Optics (including laser optics and quantum optics)

A resistive target probes were employed to obtain unique characteristics of the dynamic of the laser-matter interaction through the observation of a return current neutralizing the positive target charge caused by electrons definitely leaving the plasma. Experimental observations show that three phases of the laser-produced plasma are well recognized, i.e. the plasma ignition phase, active plasma phase, and afterglow phase already for the lowest laser intensity at the focal point of 10 8 Wcm2 . Then, at higher intensities the first two phases strongly dominate and the target current reaches a value of 10 kA. A throughput of plasma barrier for the fastest electrons leaving the plasma is defined, and its value is experimentally estimated. We also present key experiments proving that the duration of the electrical charge on the target is much longer than the duration of the laser-plasma interaction for the entire intensity range.
Permanent Link: http://hdl.handle.net/11104/0299500