Title: Nonequilibrium dissociative dynamics of ${\mathrm{D}}_2$ in two-color, few-photon excitation and ionization

Abstract

D₂ molecules, excited by linearly cross-polarized femtosecond extreme ultraviolet (XUV) and near-infrared (NIR) light pulses, reveal highly structured D⁺ ion fragment momenta and angular distributions that originate from two different four-step dissociative ionization pathways after four-photon absorption (one XUV + three NIR). We show that, even for very low dissociation kinetic energy release ≤ 240 meV, specific electronic excitation pathways can be identified and isolated in the final ion momentum distributions. With the aid of ab initio electronic structure and time-dependent Schrödinger equation calculations, angular momentum, energy, and parity conservation are used to identify the excited neutral molecular states and molecular orientations relative to the polarization vectors in these different photoexcitation and dissociation sequences of the neutral D₂ molecule and its $$D_2^+$$ cation. In one sequential photodissociation pathway, molecules aligned along either of the two light polarization vectors are excluded, while another pathway selects molecules aligned parallel to the light propagation direction. The evolution of the nuclear wave packet on the intermediate $$B^1Σ_u^+$$ electronic state of the neutral D₂ molecule is also probed in real time.

Authors:

Slaughter, D. S. ;

• Search DOE PAGES for author "Slaughter, D. S."
• Search DOE PAGES for ORCID "0000-0002-4621-4552"

Sturm, F. P.; Bello, Roger Y. ;

• Search DOE PAGES for author "Bello, Roger Y."
• Search DOE PAGES for ORCID "0000-0001-9576-6479"

Larsen, K. A.; Shivaram, N. ;

• Search DOE PAGES for author "Shivaram, N."
• Search DOE PAGES for ORCID "0000-0002-9550-3588"

McCurdy, C. W.; Lucchese, R. R.; Martin, L.; Hogle, C. W.; Murnane, M. M.; Kapteyn, H. C.; Ranitovic, P.; Weber, Th.

• Search DOE PAGES for author "Weber, Th."
• Search DOE PAGES for ORCID "0000-0003-3756-2704"

Publication Date:

Thu Aug 26 00:00:00 EDT 2021

Research Org.:

Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Univ. of Colorado, Boulder, CO (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

2325368

Alternate Identifier(s):

OSTI ID: 1825502; OSTI ID: 1907860

Grant/Contract Number:  

AC02-05CH11231; FG02-99ER14982

Resource Type:

Published Article

Journal Name:

Physical Review Research

Additional Journal Information:

Journal Name: Physical Review Research Journal Volume: 3 Journal Issue: 3; Journal ID: ISSN 2643-1564

Publisher:

American Physical Society

Country of Publication:

United States

Language:

English

Subject:

74 ATOMIC AND MOLECULAR PHYSICS; electronic excitation & ionization; electronic transitions; high-order harmonic generation; interatomic & molecular potentials; molecular spectra; multiphoton or tunneling ionization & excitation; photodissociation; potential energy surfaces; single- and few-photon ionization & excitation; ultrafast phenomena; electronic structure; molecular dynamics; photoexcitation; photoionization; Schroedinger equation