Quantum and quasi-classical effects in the strong field ionization and subsequent excitation of nitrogen molecules

0572554 - FZÚ 2024 RIV US eng J - Journal Article
Xu, L. - Lu, Q. - Tikhonchuk, Vladimir - Zhou, B. - Yang, R. - Liang, Q. - He, F. - Danylo, R. - Houard, A. - Mysyrowicz, A. - Liu, Y.
Quantum and quasi-classical effects in the strong field ionization and subsequent excitation of nitrogen molecules.
Optics Express. Roč. 30, č. 21 (2022), č. článku 38481. ISSN 1094-4087
Institutional support: RVO:68378271
Keywords : laser
OECD category: Optics (including laser optics and quantum optics)
Impact factor: 3.8, year: 2022
Method of publishing: Open access

The processes leading to the N-2(+) lasing are rather complex and even the population distribution after the pump laser excitation is unknown. In this paper, we study the population distribution at electronic and vibrational levels in N-2(+) driven by ultra-short laser pulse at the wavelengths of 800 nm and 400 nm by using the quantum-mechanical time-domain incoherent superposition model based on the time-dependent Schrodinger equation and the quasi-classical model assuming instantaneous ionization injection described by density matrix. It is shown that while both models provide qualitatively similar results, the quasi-classical instantaneous ionization injection model underestimates the population inversions corresponding to the optical transitions at 391 nm, 423 nm and 428 nm due to the assumption of quantum mixed states at the ionization time. A fast and accurate correction to this error is proposed.
Permanent Link: https://hdl.handle.net/11104/0343207