Subthreshold Erosion of an Organic Polymer Induced by Multiple Shots of an X-Ray Free-Electron Laser

0534838 - ÚFCH JH 2021 RIV US eng J - Článek v odborném periodiku
Burian, Tomáš - Chalupský, J. - Hájková, V. - Toufarová, M. - Vorlíček, V. - Hau-Riege, S. - Krzywinski, J. - Bozek, J.D. - Bostedt, C. - Graf, A.T. - Jastrow, U.F. - Kreis, S. - London, R.A. - Messerschmidt, M. - Moeller, S. - Sobierajski, R. - Tiedtke, K. - De Grazia, M. - Auguste, T. - Carré, B. - Guizard, S. - Merdji, H. - Medvedev, N. - Juha, L.
Subthreshold Erosion of an Organic Polymer Induced by Multiple Shots of an X-Ray Free-Electron Laser.
Physical Review Applied. Roč. 14, č. 3 (2020), č. článku 034057. ISSN 2331-7019. E-ISSN 2331-7019
Grant CEP: GA ČR GA19-03314S
GRANT EU: European Commission(XE) 829153
Institucionální podpora: RVO:61388955
Klíčová slova: damage threshold * radiation-damage * pulses * ablation * transmission * reflection
Obor OECD: Physical chemistry
Impakt faktor: 4.985, rok: 2020
Způsob publikování: Omezený přístup

Solids irradiated by energetic photons can be eroded in two modes, depending on the radiation intensity. High average, low-peak power sources, e.g., synchrotron radiation and high-order harmonics, induce desorption of the material at a low etch rate. In contrast, high-peak-power radiation from extreme ultraviolet and x-ray lasers usually causes a massive removal of the material even by a single shot. In this contribution, an effective material erosion is reported in PMMA exposed to multiple accumulated pulses generated by the free-electron x-ray-laser Linac Coherent Light Source (LCLS, tuned at a photon energy of 830 eV in this study, operated in Menlo Park at Stanford, CA, USA) at a fluence below the single-pulse ablation threshold. The effect is caused by polymer-chain scissions initiated by single photons carrying enough energy to break the C-C bounds. High efficiency of the erosion is supposed to occur due to a correlation of the single-photon effects. The subthreshold damage exhibits a nonlinear dose dependence resulting from a competition between chain scissions and cross-linking processes. The cross-linking is proven by Raman spectroscopy of the irradiated polymer. Two theoretical models of the x-ray free-electron-laser-induced erosion are suggested, which provide an excellent agreement with the experimental results.
Trvalý link: http://hdl.handle.net/11104/0313002