Laser control over the ultrafast Coulomb explosion of $N_2{}^{2+}$ after Auger decay: A quantum-dynamics investigation

Journal Article · Mon Apr 24 00:00:00 EDT 2017 · Physical Review A

DOI:https://doi.org/10.1103/PhysRevA.95.043419· OSTI ID:1598189

Hanna, Athiya Mahmud ^[1]; Vendrell, Oriol ^[2]; Ourmazd, Abbas ^[3]; Santra, Robin ^[4]

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1. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Univ. of Hamburg (Germany)
2. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Hamburg Centre for Ultrafast Imaging (Germany); Aarhus Univ. (Denmark)
3. Univ. of Wisconsin, Milwaukee, WI (United States)
4. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Univ. of Hamburg (Germany); Hamburg Centre for Ultrafast Imaging (Germany)

By theoretical calculation, we show the possibility to control and partially suppress the Coulomb explosion of ${\mathrm{N}}_2$ molecules after core-level photoionization by an x-ray laser and subsequent Auger decay. This is achieved by means of a femtosecond infrared laser pulse interacting with the ${\mathrm{N}}_2{}^{2+}$ dication produced by the x-ray pulse. Suppression of molecular fragmentation requires few-femtosecond IR pulses interacting with the system either during or shortly after the arrival of the x-ray pulse. The IR pulse suppresses fragmentation mostly by optically coupling the electronic routes to ultrafast molecular dissociation with electronic channels able to support long-lived vibrational resonances. The effect is strongly dependent on the orientation of the molecule with respect to the polarization axis of the IR field. These calculations are motivated by x-ray pump–IR probe experiments performed at an x-ray free-electron laser [J. M. Glownia et al., Opt. Express 18, 17620 (2010)], where only enhancement of ${\mathrm{N}}_2{}^{2+}$ fragmentation as a function of the pump-probe delay time was reported. The opposite effect reported here becomes apparent when the various electronic channels are considered separately. In practice, this corresponds to a coincident measurement of the energy of the ejected Auger electron

• Research Organization: Univ. of Wisconsin, Milwaukee, WI (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0002164
• OSTI ID: 1598189
• Alternate ID(s): OSTI ID: 1352965
• Journal Information: Physical Review A, Vol. 95, Issue 4; ISSN 2469-9926
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS