Phase-matched high-order harmonic generation in pre-ionized noble gases

0557655 - FZÚ 2023 RIV GB eng J - Journal Article
Finke, Ondřej - Vábek, Jan - Nevrkla, Michal - Bobrova, N. - Hort, Ondřej - Jurkovič, Matěj - Albrecht, Martin - Jančárek, Alexandr - Catoire, F. - Skupin, S. - Nejdl, Jaroslav
Phase-matched high-order harmonic generation in pre-ionized noble gases.
Scientific Reports. Roč. 12, č. 1 (2022), č. článku 7715. ISSN 2045-2322. E-ISSN 2045-2322
R&D Projects: GA MŠMT EF16_019/0000789
Grant - others:OP VVV - ADONIS(XE) CZ.02.1.01/0.0/0.0/16_019/0000789
Research Infrastructure: ELI Beamlines III - 90141
Institutional support: RVO:68378271
Keywords : high-order harmonic generation * capillary discharge
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 4.6, year: 2022
Method of publishing: Open access

One of the main difficulties of efficiently generating high-order harmonics in long neutral-gas targets is to reach the phase-matching conditions. The issue is that the medium cannot be sufficiently ionized by the driving laser due to plasma defocusing. We propose a method to improve the phase-matching by pre-ionizing the gas using a weak capillary discharge. We have demonstrated this mechanism, for the first time, in absorption-limited XUV generation by an 800 nm femtosecond laser in argon and krypton. The ability to control phase-mismatch is confirmed by an analytical model and numerical simulations of the entire generation process. Our method allows to increase the efficiency of the harmonic generation significantly, paving the way towards photon-hungry applications of these compact short-wavelength sources.
Permanent Link: http://hdl.handle.net/11104/0331575