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  • Open Access

Asymmetry in orientation-resolved strong-field ionization of polar molecules

Mahmoud Abu-samha1,* and Lars Bojer Madsen2

  • 1College of Integrative Studies, Abdullah Al Salem University, Khaldiya, Kuwait
  • 2Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark

  • *Contact author: Mahmoud.abusamha@aasu.edu.kw
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Phys. Rev. Research 7, 043172 – Published 17 November, 2025

DOI: https://doi.org/10.1103/qlsh-7rnk

Abstract

We present calculations of orientation-dependent ionization yields from aligned H2+ and oriented polar HeH2+ and CO molecules by simulating the three-dimensional time-dependent Schrödinger equation. For the polar molecules, we observe asymmetries in orientation-resolved total ionization yields: The yields are not reflection symmetric across the orientation angle β=90∘ with respect to the axis of the linear polarization of the laser field. A simple ionization model, applicable in the tunneling ionization regime, explains the asymmetry in ionization yields based on structural factors from weak-field asymptotic tunneling theory and asymmetries in the external field.

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Phys. Rev. Research 7, 043172– Published 17 November, 2025
  • Received 22 September 2025
  • Accepted 31 October 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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