Influence of tunnel ionization to third-harmonic generation of infrared femtosecond laser pulses in air

authored by
Viktorija Tamulienė, Greta Juškevičiūtė, Danas Buožius, Virgilijus Vaičaitis, Ihar Babushkin, Uwe Morgner
Abstract

Here we present an experimental as well as theoretical study of third-harmonic generation in tightly focused femtosecond filaments in air at the wavelength of 1.5μm. At low intensities, longitudinal phase matching is dominating in the formation of 3rd harmonics, whereas at higher intensities locked X-waves are formed. We provide the arguments that the X-wave formation is governed mainly by the tunnel-like ionization dynamics rather than by the multiphoton one. Despite of this fact, the impact of the ionization-induced nonlinearity is lower than the one from bound–bound transitions at all intensities.

Organisation(s)
Institute of Quantum Optics
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines
External Organisation(s)
Vilnius University
Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy im Forschungsbund Berlin e.V. (MBI)
Type
Article
Journal
Scientific reports
Volume
10
ISSN
2045-2322
Publication date
15.10.2020
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
General
Electronic version(s)
https://doi.org/10.1038/s41598-020-74263-x (Access: Open)