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Voznyuk O, Jochim B, Zohrabi M, Broin A, Averin R, Carnes KD, Ben-Itzhak I, Wells E. Adaptive strong-field control of vibrational population in NO 2+. J Chem Phys 2019; 151:124310. [DOI: 10.1063/1.5115504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- O. Voznyuk
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
| | - Bethany Jochim
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - M. Zohrabi
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - Adam Broin
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
| | - R. Averin
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
| | - K. D. Carnes
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - I. Ben-Itzhak
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - E. Wells
- Department of Physics, Augustana University, Sioux Falls, South Dakota 57197, USA
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Jochim B, Berry B, Severt T, Feizollah P, Zohrabi M, P KR, Wells E, Carnes KD, Ben-Itzhak I. Dependence on the Initial Configuration of Strong Field-Driven Isomerization of C 2H 2 Cations and Anions. J Phys Chem Lett 2019; 10:2320-2327. [PMID: 31002520 DOI: 10.1021/acs.jpclett.9b00520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We have investigated the femtosecond laser-induced fragmentation of C2H2 q ion beam targets in various initial configurations, including acetylene (linear HCCH), vinylidene (H2CC), and cis/ trans. The initial configuration is shown to have a tremendous impact on the branching ratio of acetylene-like (CH q1 + CH q2) and vinylidene-like (C q1' + CH2 q2') dissociation of a specific C2H2 q molecular ion. In particular, whereas C2H2+ generated from C2H2, a linear HCCH target, exhibits comparable levels of acetylene-like and vinylidene-like fragmentation, vinylidene or cis/ trans configuration ion beams preferably undergo vinylidene-like fragmentation, with an acetylene branching ratio ranging from 13.9% to zero.
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Affiliation(s)
- Bethany Jochim
- J. R. Macdonald Laboratory, Department of Physics , Kansas State University , Manhattan , Kansas 66506 , United States
| | - Ben Berry
- J. R. Macdonald Laboratory, Department of Physics , Kansas State University , Manhattan , Kansas 66506 , United States
| | - T Severt
- J. R. Macdonald Laboratory, Department of Physics , Kansas State University , Manhattan , Kansas 66506 , United States
| | - Peyman Feizollah
- J. R. Macdonald Laboratory, Department of Physics , Kansas State University , Manhattan , Kansas 66506 , United States
| | - M Zohrabi
- J. R. Macdonald Laboratory, Department of Physics , Kansas State University , Manhattan , Kansas 66506 , United States
| | - Kanaka Raju P
- J. R. Macdonald Laboratory, Department of Physics , Kansas State University , Manhattan , Kansas 66506 , United States
| | - E Wells
- Department of Physics , Augustana University , Sioux Falls , South Dakota 57197 , United States
| | - K D Carnes
- J. R. Macdonald Laboratory, Department of Physics , Kansas State University , Manhattan , Kansas 66506 , United States
| | - I Ben-Itzhak
- J. R. Macdonald Laboratory, Department of Physics , Kansas State University , Manhattan , Kansas 66506 , United States
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Malakar Y, Pearson WL, Zohrabi M, Kaderiya B, P. KR, Ziaee F, Xue S, Le AT, Ben-Itzhak I, Rolles D, Rudenko A. Time-resolved imaging of bound and dissociating nuclear wave packets in strong-field ionized iodomethane. Phys Chem Chem Phys 2019; 21:14090-14102. [DOI: 10.1039/c8cp07032f] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the results of a time-resolved coincident ion momentum imaging experiment probing nuclear wave packet dynamics in the strong-field ionization and dissociation of iodomethane (CH3I).
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Rajput J, Severt T, Berry B, Jochim B, Feizollah P, Kaderiya B, Zohrabi M, Ablikim U, Ziaee F, Raju P K, Rolles D, Rudenko A, Carnes KD, Esry BD, Ben-Itzhak I. Native Frames: Disentangling Sequential from Concerted Three-Body Fragmentation. Phys Rev Lett 2018; 120:103001. [PMID: 29570318 DOI: 10.1103/physrevlett.120.103001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Indexed: 06/08/2023]
Abstract
A key question concerning the three-body fragmentation of polyatomic molecules is the distinction of sequential and concerted mechanisms, i.e., the stepwise or simultaneous cleavage of bonds. Using laser-driven fragmentation of OCS into O^{+}+C^{+}+S^{+} and employing coincidence momentum imaging, we demonstrate a novel method that enables the clear separation of sequential and concerted breakup. The separation is accomplished by analyzing the three-body fragmentation in the native frame associated with each step and taking advantage of the rotation of the intermediate molecular fragment, CO^{2+} or CS^{2+}, before its unimolecular dissociation. This native-frame method works for any projectile (electrons, ions, or photons), provides details on each step of the sequential breakup, and enables the retrieval of the relevant spectra for sequential and concerted breakup separately. Specifically, this allows the determination of the branching ratio of all these processes in OCS^{3+} breakup. Moreover, we find that the first step of sequential breakup is tightly aligned along the laser polarization and identify the likely electronic states of the intermediate dication that undergo unimolecular dissociation in the second step. Finally, the separated concerted breakup spectra show clearly that the central carbon atom is preferentially ejected perpendicular to the laser field.
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Affiliation(s)
- Jyoti Rajput
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - T Severt
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - Ben Berry
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - Bethany Jochim
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - Peyman Feizollah
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - Balram Kaderiya
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - M Zohrabi
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - U Ablikim
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - Farzaneh Ziaee
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - Kanaka Raju P
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - D Rolles
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - A Rudenko
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - K D Carnes
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - B D Esry
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - I Ben-Itzhak
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
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5
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Jochim B, Siemering R, Zohrabi M, Voznyuk O, Mahowald JB, Schmitz DG, Betsch KJ, Berry B, Severt T, Kling NG, Burwitz TG, Carnes KD, Kling MF, Ben-Itzhak I, Wells E, de Vivie-Riedle R. The importance of Rydberg orbitals in dissociative ionization of small hydrocarbon molecules in intense laser fields. Sci Rep 2017; 7:4441. [PMID: 28667335 PMCID: PMC5493692 DOI: 10.1038/s41598-017-04638-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 05/18/2017] [Indexed: 11/10/2022] Open
Abstract
Much of our intuition about strong-field processes is built upon studies of diatomic molecules, which typically have electronic states that are relatively well separated in energy. In polyatomic molecules, however, the electronic states are closer together, leading to more complex interactions. A combined experimental and theoretical investigation of strong-field ionization followed by hydrogen elimination in the hydrocarbon series C2D2, C2D4 and C2D6 reveals that the photofragment angular distributions can only be understood when the field-dressed orbitals rather than the field-free orbitals are considered. Our measured angular distributions and intensity dependence show that these field-dressed orbitals can have strong Rydberg character for certain orientations of the molecule relative to the laser polarization and that they may contribute significantly to the hydrogen elimination dissociative ionization yield. These findings suggest that Rydberg contributions to field-dressed orbitals should be routinely considered when studying polyatomic molecules in intense laser fields.
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Affiliation(s)
- Bethany Jochim
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA
| | - R Siemering
- Department für Chemie, Ludwig-Maximilians-Universität München, Butenandt-Strasse 11, D-81377, München, Germany
| | - M Zohrabi
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA
| | - O Voznyuk
- Department of Physics, Augustana University, Sioux Falls, SD 57197, USA
| | - J B Mahowald
- Department of Physics, Augustana University, Sioux Falls, SD 57197, USA
| | - D G Schmitz
- Department of Physics, Augustana University, Sioux Falls, SD 57197, USA
| | - K J Betsch
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA
| | - Ben Berry
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA
| | - T Severt
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA
| | - Nora G Kling
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA.,Department für Physik, Ludwig-Maximilians-Universität München, Am Coulombwall 1, D-85748, Garching, Germany
| | - T G Burwitz
- Department of Physics, Augustana University, Sioux Falls, SD 57197, USA
| | - K D Carnes
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA
| | - M F Kling
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA.,Department für Physik, Ludwig-Maximilians-Universität München, Am Coulombwall 1, D-85748, Garching, Germany
| | - I Ben-Itzhak
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA
| | - E Wells
- Department of Physics, Augustana University, Sioux Falls, SD 57197, USA.
| | - R de Vivie-Riedle
- Department für Chemie, Ludwig-Maximilians-Universität München, Butenandt-Strasse 11, D-81377, München, Germany.
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Berry B, Zohrabi M, Hayes D, Ablikim U, Jochim B, Severt T, Carnes KD, Ben-Itzhak I. Note: Determining the detection efficiency of excited neutral atoms by a microchannel plate detector. Rev Sci Instrum 2015; 86:046103. [PMID: 25933901 DOI: 10.1063/1.4916953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present a method for determining the detection efficiency of neutral atoms relative to keV ions. Excited D* atoms are produced by D2 fragmentation in a strong laser field. The fragments are detected by a micro-channel plate detector either directly as neutrals or as keV ions following field ionization and acceleration by a static electric field. Moreover, we propose a new mechanism by which neutrals are detected. We show that the ratio of the yield of neutrals and ions can be related to the relative detection efficiency of these species.
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Affiliation(s)
- Ben Berry
- J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - M Zohrabi
- J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - D Hayes
- J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - U Ablikim
- J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - Bethany Jochim
- J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - T Severt
- J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - K D Carnes
- J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - I Ben-Itzhak
- J.R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
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7
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Ablikim U, Zohrabi M, Jochim B, Berry B, Severt T, Carnes KD, Ben-Itzhak I. Note: Position dependence of time signals picked off a microchannel plate detector. Rev Sci Instrum 2015; 86:016111. [PMID: 25638138 DOI: 10.1063/1.4906327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 01/08/2015] [Indexed: 06/04/2023]
Abstract
Using an ultrafast laser and a precision mask, we demonstrate that time signals picked off directly from a microchannel plate detector depend on the position of the hit. This causes a time spread of about 280 ps, which can affect the quality of imaging measurements using large detectors.
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Affiliation(s)
- U Ablikim
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - M Zohrabi
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - Bethany Jochim
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - B Berry
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - T Severt
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - K D Carnes
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
| | - I Ben-Itzhak
- J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, Kansas 66506, USA
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Rallis CE, Burwitz TG, Andrews PR, Zohrabi M, Averin R, De S, Bergues B, Jochim B, Voznyuk AV, Gregerson N, Gaire B, Znakovskaya I, McKenna J, Carnes KD, Kling MF, Ben-Itzhak I, Wells E. Incorporating real time velocity map image reconstruction into closed-loop coherent control. Rev Sci Instrum 2014; 85:113105. [PMID: 25430096 DOI: 10.1063/1.4899267] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report techniques developed to utilize three-dimensional momentum information as feedback in adaptive femtosecond control of molecular dynamics. Velocity map imaging is used to obtain the three-dimensional momentum map of the dissociating ions following interaction with a shaped intense ultrafast laser pulse. In order to recover robust feedback information, however, the two-dimensional momentum projection from the detector must be inverted to reconstruct the full three-dimensional momentum of the photofragments. These methods are typically slow or require manual inputs and are therefore accomplished offline after the images have been obtained. Using an algorithm based upon an "onion-peeling" (also known as "back projection") method, we are able to invert 1040 × 1054 pixel images in under 1 s. This rapid inversion allows the full photofragment momentum to be used as feedback in a closed-loop adaptive control scheme, in which a genetic algorithm tailors an ultrafast laser pulse to optimize a specific outcome. Examples of three-dimensional velocity map image based control applied to strong-field dissociation of CO and O2 are presented.
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Affiliation(s)
- C E Rallis
- Department of Physics, Augustana College, Sioux Falls, South Dakota 57197, USA
| | - T G Burwitz
- Department of Physics, Augustana College, Sioux Falls, South Dakota 57197, USA
| | - P R Andrews
- Department of Physics, Augustana College, Sioux Falls, South Dakota 57197, USA
| | - M Zohrabi
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - R Averin
- Department of Physics, Augustana College, Sioux Falls, South Dakota 57197, USA
| | - S De
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - B Bergues
- Max Planck Institute of Quantum Optics, Hans-Kopfermann Strasse 1, D-85748 Garching, Germany
| | - Bethany Jochim
- Department of Physics, Augustana College, Sioux Falls, South Dakota 57197, USA
| | - A V Voznyuk
- Department of Physics, Augustana College, Sioux Falls, South Dakota 57197, USA
| | - Neal Gregerson
- Department of Physics, Augustana College, Sioux Falls, South Dakota 57197, USA
| | - B Gaire
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - I Znakovskaya
- Max Planck Institute of Quantum Optics, Hans-Kopfermann Strasse 1, D-85748 Garching, Germany
| | - J McKenna
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - K D Carnes
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - M F Kling
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - I Ben-Itzhak
- J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - E Wells
- Department of Physics, Augustana College, Sioux Falls, South Dakota 57197, USA
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Wells E, Rallis C, Zohrabi M, Siemering R, Jochim B, Andrews P, Ablikim U, Gaire B, De S, Carnes K, Bergues B, de Vivie-Riedle R, Kling M, Ben-Itzhak I. Adaptive strong-field control of chemical dynamics guided by three-dimensional momentum imaging. Nat Commun 2013; 4:2895. [DOI: 10.1038/ncomms3895] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 11/07/2013] [Indexed: 11/09/2022] Open
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Kling NG, Betsch KJ, Zohrabi M, Zeng S, Anis F, Ablikim U, Jochim B, Wang Z, Kübel M, Kling MF, Carnes KD, Esry BD, Ben-Itzhak I. Carrier-envelope phase control over pathway interference in strong-field dissociation of H2+. Phys Rev Lett 2013; 111:163004. [PMID: 24182264 DOI: 10.1103/physrevlett.111.163004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Indexed: 06/02/2023]
Abstract
The dissociation of an H2+ molecular-ion beam by linearly polarized, carrier-envelope-phase-tagged 5 fs pulses at 4×10(14) W/cm2 with a central wavelength of 730 nm was studied using a coincidence 3D momentum imaging technique. Carrier-envelope-phase-dependent asymmetries in the emission direction of H+ fragments relative to the laser polarization were observed. These asymmetries are caused by interference of odd and even photon number pathways, where net zero-photon and one-photon interference predominantly contributes at H+ + H kinetic energy releases of 0.2-0.45 eV, and net two-photon and one-photon interference contributes at 1.65-1.9 eV. These measurements of the benchmark H2+ molecule offer the distinct advantage that they can be quantitatively compared with ab initio theory to confirm our understanding of strong-field coherent control via the carrier-envelope phase.
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Affiliation(s)
- Nora G Kling
- J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
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McKenna J, Anis F, Gaire B, Johnson NG, Zohrabi M, Carnes KD, Esry BD, Ben-Itzhak I. Suppressed dissociation of H(2)(+) vibrational states by reduced dipole coupling. Phys Rev Lett 2009; 103:103006. [PMID: 19792305 DOI: 10.1103/physrevlett.103.103006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Indexed: 05/28/2023]
Abstract
The suppression of H(2)(+) strong-field dissociation has intrigued experimentalists and theorists since the early days of laser-molecular science. We unravel a vibrational suppression effect due to weak dipole-matrix element coupling strengths of certain vibrational states, dependent on the laser frequency-a form of Cooper minima. This effect is demonstrated by our full-dimensional calculations on H(2)(+) dissociation and persists for a broad range of laser conditions including both weak and strong-field dissociation. Using a crossed-beams coincidence, three-dimensional momentum-imaging technique, the vibrational suppression effect is clearly observed for H(2)(+) and HD(+) at 790 and 395 nm, in good agreement with our theory.
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Affiliation(s)
- J McKenna
- J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
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