1
|
Guo Z, Zhang Z, Deng Y, Wang J, Ye D, Liu J, Liu Y. Probing H_{2} Double Ionization with Bicircular Laser Fields. PHYSICAL REVIEW LETTERS 2024; 132:143201. [PMID: 38640361 DOI: 10.1103/physrevlett.132.143201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 11/30/2023] [Accepted: 03/14/2024] [Indexed: 04/21/2024]
Abstract
We present a kinematically complete study on strong-field double ionization of H_{2} molecules in two-color bicircular laser fields. The releasing times of electrons and protons are recorded with the double-hand attoclock. We observe the relative emission angles of two electrons oscillate with the kinetic energy release of protons, indicating the internal concerted four-body fragmentation. Using a three-dimensional molecular semiclassical ensemble model, we have disentangled the attosecond correlated electron emission in H_{2} double ionization. This work reveals the strong electron-nuclear coupling in the molecular bond breaking and may open up a new approach to experimentally accessing the intramolecular electron and bond dynamics with bicircular fields.
Collapse
Affiliation(s)
- Zhenning Guo
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Zhihe Zhang
- Center for Applied Physics and Technology, HEDPS, Peking University, Beijing 100871, China
| | - Yongkai Deng
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Jiguo Wang
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
| | - Difa Ye
- National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
| | - Jie Liu
- Center for Applied Physics and Technology, HEDPS, Peking University, Beijing 100871, China
- Graduate School, China Academy of Engineering Physics, Beijing 100193, China
| | - Yunquan Liu
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China
- Center for Applied Physics and Technology, HEDPS, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
| |
Collapse
|
2
|
Trabert D, Anders N, Brennecke S, Schöffler MS, Jahnke T, Schmidt LPH, Kunitski M, Lein M, Dörner R, Eckart S. Nonadiabatic Strong Field Ionization of Atomic Hydrogen. PHYSICAL REVIEW LETTERS 2021; 127:273201. [PMID: 35061406 DOI: 10.1103/physrevlett.127.273201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 12/07/2021] [Indexed: 06/14/2023]
Abstract
We present experimental data on the nonadiabatic strong field ionization of atomic hydrogen using elliptically polarized femtosecond laser pulses at a central wavelength of 390 nm. Our measured results are in very good agreement with a numerical solution of the time-dependent Schrödinger equation (TDSE). Experiment and TDSE show four above-threshold ionization peaks in the electron's energy spectrum. The most probable emission angle (also known as "attoclock offset angle" or "streaking angle") is found to increase with energy, a trend that is opposite to standard predictions based on Coulomb interaction with the ion. We show that this increase of deflection angle can be explained by a model that includes nonadiabatic corrections of the initial momentum distribution at the tunnel exit and nonadiabatic corrections of the tunnel exit position itself.
Collapse
Affiliation(s)
- D Trabert
- Institut für Kernphysik, Goethe-Universität, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
| | - N Anders
- Institut für Kernphysik, Goethe-Universität, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
| | - S Brennecke
- Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover, Germany
| | - M S Schöffler
- Institut für Kernphysik, Goethe-Universität, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
| | - T Jahnke
- Institut für Kernphysik, Goethe-Universität, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
| | - L Ph H Schmidt
- Institut für Kernphysik, Goethe-Universität, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
| | - M Kunitski
- Institut für Kernphysik, Goethe-Universität, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
| | - M Lein
- Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover, Germany
| | - R Dörner
- Institut für Kernphysik, Goethe-Universität, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
| | - S Eckart
- Institut für Kernphysik, Goethe-Universität, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany
| |
Collapse
|
3
|
|
4
|
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] [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.
Collapse
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
| |
Collapse
|
5
|
Ekanayake N, Nairat M, Weingartz NP, Michie MJ, Levine BG, Dantus M. Substituent effects on H 3 + formation via H 2 roaming mechanisms from organic molecules under strong-field photodissociation. J Chem Phys 2018; 149:244310. [PMID: 30599731 DOI: 10.1063/1.5065387] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Roaming chemical reactions are often associated with neutral molecules. The recent findings of roaming processes in ionic species, in particular, ones that lead to the formation of H3 + under strong-field laser excitation, are of considerable interest. Given that such gas-phase reactions are initiated by double ionization and subsequently facilitated through deprotonation, we investigate the strong-field photodissociation of ethanethiol, also known as ethyl mercaptan, and compare it to results from ethanol. Contrary to expectations, the H3 + yield was found to be an order of magnitude lower for ethanethiol at certain laser field intensities, despite its lower ionization energy and higher acidity compared to ethanol. In-depth analysis of the femtosecond time-resolved experimental findings, supported by ab initio quantum mechanical calculations, provides key information regarding the roaming mechanisms related to H3 + formation. Results of this study on the dynamics of dissociative half-collisions involving H3 +, a vital cation which acts as a Brønsted-Lowry acid protonating interstellar organic compounds, may also provide valuable information regarding the formation mechanisms and observed natural abundances of complex organic molecules in interstellar media and planetary atmospheres.
Collapse
Affiliation(s)
- Nagitha Ekanayake
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Muath Nairat
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Nicholas P Weingartz
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Matthew J Michie
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Benjamin G Levine
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Marcos Dantus
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| |
Collapse
|
6
|
Non-sequential double ionization with near-single cycle laser pulses. Sci Rep 2017; 7:7488. [PMID: 28790410 PMCID: PMC5548909 DOI: 10.1038/s41598-017-07635-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 06/30/2017] [Indexed: 11/08/2022] Open
Abstract
A three-dimensional semiclassical model is used to study double ionization of Ar when driven by a near-infrared and near-single-cycle laser pulse for intensities ranging from 0.85 × 1014 W/cm2 to 5 × 1014 W/cm2. Asymmetry parameters, distributions of the sum of the two electron momentum components along the direction of the polarization of the laser field and correlated electron momenta are computed as a function of the intensity and of the carrier envelope phase. A very good agreement is found with recently obtained results in kinematically complete experiments employing near-single-cycle laser pulses. Moreover, the contribution of the direct and delayed pathways of double ionization is investigated for the above observables. Finally, an experimentally obtained anti-correlation momentum pattern at higher intensities is reproduced with the three-dimensional semiclassical model and shown to be due to a transition from strong to soft recollisions with increasing intensity.
Collapse
|
7
|
Zhou Y, Li M, Li Y, Tong A, Li Q, Lu P. Dissection of electron correlation in strong-field sequential double ionization using a classical model. OPTICS EXPRESS 2017; 25:8450-8458. [PMID: 28380956 DOI: 10.1364/oe.25.008450] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Recent experiments on strong-field sequential double ionization (SDI) have reported several observations which are regarded as evidence of electron correlation, querying the validity of the standard independent electron approximation for SDI. Here we theoretically study SDI with a classical ensemble model. The experimental results are well reproduced with this model. Back tracing of the ionization process shows that these results are ascribed to the subcycle ionization dynamics of the two electrons, not the evidences of the electron correlation in SDI. Thus, the previously reported observations are not enough to claim the breakdown of the independent electron approximation in SDI.
Collapse
|
8
|
Nairat M, Lozovoy VV, Dantus M. Order of Magnitude Dissociative Ionization Enhancement Observed for Pulses with High Order Dispersion. J Phys Chem A 2016; 120:8529-8536. [PMID: 27744700 DOI: 10.1021/acs.jpca.6b08659] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
While the interaction of atoms in strong fields is well understood, the same cannot be said about molecules. We consider how dissociative ionization of molecules depends on the quality of the femtosecond laser pulses, in particular, the presence of third- and fourth-order dispersion. We find that high-order dispersion (HOD) unexpectedly results in order-of-magnitude enhanced ion yields, along with the factor of 3 greater kinetic energy release compared to transform-limited pulses with equal peak intensities. The magnitude of these effects is not caused by increased pulse duration. We evaluate the role of pulse pedestals produced by HOD and other pulse shaping approaches, for a number of molecules including acetylene, methanol, methylene chloride, acetonitrile, toluene, and o-nitrotoluene, and discuss our findings in terms of processes such as prealignment, preionization, and bond softening. We conclude, based on the quasi-symmetric temporal dependence of the observed enhancements that cascade ionization is likely responsible for the large accumulation of charge prior to the ejection of energetic fragments along the laser polarization axis.
Collapse
Affiliation(s)
- Muath Nairat
- Department of Chemistry, Michigan State University , East Lansing, Michigan 48824, United States
| | - Vadim V Lozovoy
- Department of Chemistry, Michigan State University , East Lansing, Michigan 48824, United States
| | - Marcos Dantus
- Department of Chemistry, Michigan State University , East Lansing, Michigan 48824, United States.,Department of Physics and Astronomy, Michigan State University , East Lansing, Michigan 48824, United States
| |
Collapse
|
9
|
Konar A, Shu Y, Lozovoy VV, Jackson JE, Levine BG, Dantus M. Polyatomic molecules under intense femtosecond laser irradiation. J Phys Chem A 2014; 118:11433-50. [PMID: 25314590 DOI: 10.1021/jp505498t] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Interaction of intense laser pulses with atoms and molecules is at the forefront of atomic, molecular, and optical physics. It is the gateway to powerful new tools that include above threshold ionization, high harmonic generation, electron diffraction, molecular tomography, and attosecond pulse generation. Intense laser pulses are ideal for probing and manipulating chemical bonding. Though the behavior of atoms in strong fields has been well studied, molecules under intense fields are not as well understood and current models have failed in certain important aspects. Molecules, as opposed to atoms, present confounding possibilities of nuclear and electronic motion upon excitation. The dynamics and fragmentation patterns in response to the laser field are structure sensitive; therefore, a molecule cannot simply be treated as a "bag of atoms" during field induced ionization. In this article we present a set of experiments and theoretical calculations exploring the behavior of a large collection of aryl alkyl ketones when irradiated with intense femtosecond pulses. Specifically, we consider to what extent molecules retain their molecular identity and properties under strong laser fields. Using time-of-flight mass spectrometry in conjunction with pump-probe techniques we study the dynamical behavior of these molecules, monitoring ion yield modulation caused by intramolecular motions post ionization. The set of molecules studied is further divided into smaller sets, sorted by type and position of functional groups. The pump-probe time-delay scans show that among positional isomers the variations in relative energies, which amount to only a few hundred millielectronvolts, influence the dynamical behavior of the molecules despite their having experienced such high fields (V/Å). High level ab initio quantum chemical calculations were performed to predict molecular dynamics along with single and multiphoton resonances in the neutral and ionic states. We propose the following model of strong-field ionization and subsequent fragmentation for polyatomic molecules: Single electron ionization occurs on a suboptical cycle time scale, and the electron carries away essentially all of the energy, leaving behind little internal energy in the cation. Subsequent fragmentation of the cation takes place as a result of further photon absorption modulated by one- and two-photon resonances, which provide sufficient energy to overcome the dissociation energy. The proposed hypothesis implies the loss of a photoelectron at a rate that is faster than intramolecular vibrational relaxation and is consistent with the observation of nonergodic photofragmentation of polyatomic molecules as well as experimental results from many other research groups on different molecules and with different pulse durations and wavelengths.
Collapse
Affiliation(s)
- Arkaprabha Konar
- Department of Chemistry and ‡Department of Physics and Astronomy, Michigan State University , East Lansing, Michigan 48824, United States
| | | | | | | | | | | |
Collapse
|
10
|
Anis F, Esry BD. Enhancing the intense field control of molecular fragmentation. PHYSICAL REVIEW LETTERS 2012; 109:133001. [PMID: 23030085 DOI: 10.1103/physrevlett.109.133001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 07/02/2012] [Indexed: 06/01/2023]
Abstract
We describe a pump-probe scheme with which the spatial asymmetry of dissociating molecular fragments-as controlled by the carrier-envelope phase of an intense few-cycle laser pulse-can be enhanced by an order of magnitude or more. We illustrate the scheme using extensive, full-dimensional calculations for dissociation of H(2)(+) and include the averaging necessary for comparison with experiment.
Collapse
Affiliation(s)
- Fatima Anis
- J R Macdonald Laboratory, Kansas State University, Manhattan, Kansas 66506, USA
| | | |
Collapse
|
11
|
Lötstedt E, Kato T, Yamanouchi K. Classical dynamics of laser-driven D₃⁺. PHYSICAL REVIEW LETTERS 2011; 106:203001. [PMID: 21668225 DOI: 10.1103/physrevlett.106.203001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2011] [Indexed: 05/30/2023]
Abstract
A classical model of the triatomic D₃⁺ molecule subjected to an intense, few-cycle laser pulse is introduced. The model is capable of describing the laser-induced correlated motion of both electrons and nuclei in three dimensions, and allows us to follow the motion of the two electrons and three deuterons from the initial field-free state, during the pulse, and until the bond breaking into the final fragments. By averaging over many trajectories, we calculate the relative yields of the ionization and dissociation channels, as well as the kinetic energy release (KER) from the fragment ions. A comparison with recent experimental KER spectra shows good qualitative agreement. In addition, we find a pathway in which an emitted electron recombines into a high-lying Rydberg state, resulting in D + D⁺ + D⁺ fragments with the same KER as in the D⁺ + D⁺ + D⁺ channel.
Collapse
Affiliation(s)
- Erik Lötstedt
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| | | | | |
Collapse
|
12
|
Leth HA, Madsen LB, Mølmer K. Monte carlo wave packet theory of dissociative double ionization. PHYSICAL REVIEW LETTERS 2009; 103:183601. [PMID: 19905804 DOI: 10.1103/physrevlett.103.183601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Revised: 10/22/2009] [Indexed: 05/28/2023]
Abstract
Nuclear dynamics in strong-field double ionization processes is predicted using a stochastic Monte Carlo wave packet technique. Using input from electronic structure calculations and strong-field electron dynamics the description allows for field-dressed dynamics within a given molecule as well as transitions between several different charge states. The description is computationally efficient and applicable to a wide range of systems. As a proof of principle, theoretical nuclear kinetic energy release spectra for H2 (D2) in strong near-infrared laser pulses of 40 fs duration are compared to experiments and very good agreement is obtained.
Collapse
Affiliation(s)
- Henriette Astrup Leth
- Lundbeck Foundation Theoretical Center for Quantum System Research, Department of Physics and Astronomy, Aarhus University, 8000 Arhus C, Denmark
| | | | | |
Collapse
|
13
|
Lozovoy VV, Zhu X, Gunaratne TC, Harris DA, Shane JC, Dantus M. Control of Molecular Fragmentation Using Shaped Femtosecond Pulses. J Phys Chem A 2008; 112:3789-812. [DOI: 10.1021/jp071691p] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Vadim V. Lozovoy
- Department of Chemistry and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824
| | - Xin Zhu
- Department of Chemistry and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824
| | - Tissa C. Gunaratne
- Department of Chemistry and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824
| | - D. Ahmasi Harris
- Department of Chemistry and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824
| | - Janelle C. Shane
- Department of Chemistry and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824
| | - Marcos Dantus
- Department of Chemistry and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824
| |
Collapse
|
14
|
Strohaber J, Uiterwaal CJGJ. In situ measurement of three-dimensional ion densities in focused femtosecond pulses. PHYSICAL REVIEW LETTERS 2008; 100:023002. [PMID: 18232863 DOI: 10.1103/physrevlett.100.023002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2007] [Indexed: 05/25/2023]
Abstract
We image spatial distributions of Xeq+ ions in the focus of a laser beam of ultrashort, intense pulses in all three dimensions, with a resolution of approximately 3 microm and approximately 12 microm in the two transverse directions. This allows for studying ionization processes without spatially averaging ion yields. Our in situ ion imaging is also useful to analyze focal intensity profiles and to investigate the transverse modal purity of tightly focused beams of complex light. As an example, the intensity profile of a Hermite-Gaussian beam mode HG1,0 recorded with ions is found to be in good agreement with optical images.
Collapse
Affiliation(s)
- J Strohaber
- Behlen Laboratory, Department of Physics and Astronomy, The University of Nebraska-Lincoln, City Campus, Lincoln, Nebraska 68588-0111, USA.
| | | |
Collapse
|
15
|
Ben-Itzhak I, Wang PQ, Xia JF, Sayler AM, Smith MA, Carnes KD, Esry BD. Dissociation and ionization of H+2 by ultrashort intense laser pulses probed by coincidence 3D momentum imaging. PHYSICAL REVIEW LETTERS 2005; 95:073002. [PMID: 16196777 DOI: 10.1103/physrevlett.95.073002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2005] [Indexed: 05/04/2023]
Abstract
Laser-induced dissociation and ionization of H(+)(2) were simultaneously measured using coincidence 3D momentum imaging, allowing direct separation of the two processes, even where the fragment kinetic energy is the same for both processes. The results for 45 and 135 fs 790 nm pulses with an intensity of approximately 2.5 x 10(14) W/cm(2) differ from each other much more than one would expect from previous measurements with longer pulses. Ionization was negligible for the longer pulse and was strongly aligned along the laser polarization for the shorter pulse, but showed no structure in its kinetic energy distribution. In addition, the ionization to dissociation ratio was found to be much smaller than theoretically predicted for H(+)(2).
Collapse
Affiliation(s)
- I Ben-Itzhak
- JR Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, 66506, USA
| | | | | | | | | | | | | |
Collapse
|