Contrasting behavior of covalent and molecular carbon allotropes exposed to extreme ultraviolet and soft x-ray free-electron laser radiation

0485037 - FZÚ 2018 RIV US eng J - Journal Article
Toufarová, Martina - Hájková, Věra - Chalupský, Jaromír - Burian, Tomáš - Vacík, Jiří - Vorlíček, Vladimír - Vyšín, Luděk - Gaudin, J. - Medvedev, Nikita - Ziaja, B. - Nagasono, M. - Yabashi, M. - Sobierajski, R. - Krzywinski, J. - Sinn, H. - Störmer, M. - Koláček, Karel - Tiedtke, K. - Toleikis, S. - Juha, Libor
Contrasting behavior of covalent and molecular carbon allotropes exposed to extreme ultraviolet and soft x-ray free-electron laser radiation.
Physical Review B. Roč. 96, č. 21 (2017), s. 1-11, č. článku 214101. ISSN 2469-9950. E-ISSN 2469-9969
R&D Projects: GA MŠMT LG15013; GA ČR(CZ) GA14-29772S; GA MŠMT(CZ) CZ.02.1.01/0.0/0.0/16_013/0001552; GA MŠMT EF16_013/0001552; GA MŠMT(CZ) LM2015083
Institutional support: RVO:68378271 ; RVO:61389005 ; RVO:61389021
Keywords : solid C-60 * reflection * pulses
OECD category: Fluids and plasma physics (including surface physics); Nuclear physics (UJF-V)
Impact factor: 3.813, year: 2017

All carbon materials, e.g., amorphous carbon (a-C) coatings and C-60 fullerene thin films, play an important role in short-wavelength free-electron laser (FEL) research motivated by FEL optics development and prospective nanotechnology applications. Responses of a-C and C-60 layers to the extreme ultraviolet (SPring-8Compact SASE Source in Japan) and soft x-ray (free-electron laser in Hamburg) free-electron laser radiation are investigated by Raman spectroscopy, differential interference contrast, and atomic force microscopy. A remarkable difference in the behavior of covalent (a-C) and molecular (C-60) carbonaceous solids is demonstrated under these irradiation conditions. Low thresholds for ablation of a fullerene crystal (estimated to be around 0.15 eV/atom for C-60 vs 0.9 eV/atom for a-C in terms of the absorbed dose) are caused by a low cohesive energy of fullerene crystals. An efficient mechanism of the removal of intact C-60 molecules from the irradiated crystal due to Coulomb repulsion of fullerene-cage cation radicals formed by the ionizing radiation is revealed by a detailed modeling.
Permanent Link: http://hdl.handle.net/11104/0280161