51
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Liu H, Liu Y, Fu L, Xin G, Ye D, Liu J, He XT, Yang Y, Liu X, Deng Y, Wu C, Gong Q. Low yield of near-zero-momentum electrons and partial atomic stabilization in strong-field tunneling ionization. PHYSICAL REVIEW LETTERS 2012; 109:093001. [PMID: 23002830 DOI: 10.1103/physrevlett.109.093001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Indexed: 06/01/2023]
Abstract
We measure photoelectron angular distributions of single ionization of krypton and xenon atoms by laser pulses at 1320 nm, 0.2-1.0×10(14) W/cm(2), and observe that the yield of near-zero-momentum electrons in the strong-field tunneling ionization regime is significantly suppressed. Semiclassical simulations indicate that this local ionization suppression effect can be attributed to a fraction of the tunneled electrons that are released in a certain window of the initial field phase and transverse velocity are ejected into Rydberg elliptical orbits with a frequency much smaller than that of the laser; i.e., the corresponding atoms are stabilized. These electrons with high-lying atomic orbits are thus prevented from ionization, resulting in the substantially reduced near-zero-momentum electron yield. The refined transition between the Rydberg states of the stabilized atoms has implication on the THz radiation from gas targets in strong laser fields.
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Affiliation(s)
- Hong Liu
- Department of Physics and State Key Laboratory for Mesoscopic Physics, Peking University, Beijing 100871, China
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52
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Pfeiffer AN, Cirelli C, Landsman AS, Smolarski M, Dimitrovski D, Madsen LB, Keller U. Probing the longitudinal momentum spread of the electron wave packet at the tunnel exit. PHYSICAL REVIEW LETTERS 2012; 109:083002. [PMID: 23002743 DOI: 10.1103/physrevlett.109.083002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Revised: 01/30/2012] [Indexed: 06/01/2023]
Abstract
We present an ellipticity-resolved study of momentum distributions arising from strong-field ionization of helium. The influence of the ion potential on the departing electron is considered within a semiclassical model consisting of an initial tunneling step and subsequent classical propagation. We find that the momentum distribution can be explained by including the longitudinal momentum spread of the electron at the exit from the tunnel. Our combined experimental and theoretical study provides an estimate of this momentum spread.
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Affiliation(s)
- A N Pfeiffer
- Physics Department, ETH Zurich, 8093 Zurich, Switzerland
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53
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Wang H, Wang K, Liu J, Dai H, Yang Z. Theoretical research on terahertz air-breakdown coherent detection with the transient photocurrent model. OPTICS EXPRESS 2012; 20:19264-19270. [PMID: 23038567 DOI: 10.1364/oe.20.019264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The physical mechanism for sensing broadband terahertz (THz) wave via using femtosecond (fs) laser induced gas plasma without any local accessory near the plasma, i.e. THz air breakdown coherent detection, is systemically investigated by utilizing the transient photocurrent model. Previous observed results, such as conversion from incoherent to coherent detection, can be numerically obtained. Further calculations and analysis show that it is through modification of the gas ionization process, and not acceleration of freed electrons or through a four-wave-mixing (FWM) process, that the THz waveforms can be encoded into the detected second harmonic (SH) signals.
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Affiliation(s)
- Hu Wang
- Wuhan National Laboratory for Optoelectronics, School of Optoelectronic Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
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54
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Wu CY, Yang YD, Liu YQ, Gong QH, Wu M, Liu X, Hao XL, Li WD, He XT, Chen J. Characteristic spectrum of very low-energy photoelectron from above-threshold ionization in the tunneling regime. PHYSICAL REVIEW LETTERS 2012; 109:043001. [PMID: 23006081 DOI: 10.1103/physrevlett.109.043001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 01/13/2012] [Indexed: 06/01/2023]
Abstract
We report an experimental and theoretical study of very low-energy photoelectrons in tunneling ionization process from noble gas atoms interacting with ultrashort intense infrared laser pulses. A universal peak structure with electron energy well below 1 eV in the photoelectron spectrum, corresponding to the double-hump structure in the longitudinal momentum distribution, is identified experimentally for all atomic species. Our quantum and semiclassical analysis reveal the role of long-range Coulomb potential in the production of this very low-energy peak structure.
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Affiliation(s)
- C Y Wu
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, China.
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55
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56
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Huang C, Li Z, Zhou Y, Tang Q, Liao Q, Lu P. Classical simulations of electron emissions from H2+ by circularly polarized laser pulses. OPTICS EXPRESS 2012; 20:11700-11709. [PMID: 22714158 DOI: 10.1364/oe.20.011700] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
With the classical fermion molecular dynamics model (FMD), we investigated electron emissions from H(2)(+) by circularly polarized laser pulses. The obtained electron momentum distribution clearly shows an angular shift relative to the expected direction for H(2)(+) aligned parallel to the polarization plane, which is in good agreement with the recent experimental result. By tracing the classical trajectory, we provide direct evidence for the electron delayed emission with respect to the instant when the electric field is parallel to the molecular axis, which was regarded as the origin of the angular shift in the electron momentum distribution. Furthermore, we find that the angular shift decreases with increasing the laser wavelength.
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Affiliation(s)
- Cheng Huang
- Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
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57
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Skobelev SA, Kim AV, Willi O. Generation of high-energy few-cycle laser pulses by using the ionization-induced self-compression effect. PHYSICAL REVIEW LETTERS 2012; 108:123904. [PMID: 22540585 DOI: 10.1103/physrevlett.108.123904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Revised: 12/20/2011] [Indexed: 05/31/2023]
Abstract
A mechanism behind the ionization-induced self-compression effect for ultrashort laser pulses propagating in gas-filled capillaries is proposed. It is shown that as a result of excitation of the nonlinear-plasma waveguide laser pulses producing gas ionization can be self-compressed to few-cycle duration. This effect is used for high-energy laser pulses and its scalability to J-level energies is demonstrated.
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Affiliation(s)
- S A Skobelev
- Institute of Applied Physics, Russian Academy of Sciences, 603950 Nizhny Novgorod, Russia
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58
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Lu X, Zhang XC. Generation of elliptically polarized terahertz waves from laser-induced plasma with double helix electrodes. PHYSICAL REVIEW LETTERS 2012; 108:123903. [PMID: 22540584 DOI: 10.1103/physrevlett.108.123903] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Indexed: 05/31/2023]
Abstract
By applying a helical electric field along a plasma region, a revolving electron current is formed along the plasma and an elliptically polarized far-field terahertz wave pattern is observed. The observed terahertz wave polarization reveals the remarkable role of velocity retardation between optical pulses and generated terahertz pulses in the generation process. Extensive simulations, including longitudinal propagation effects, are performed to clarify the mechanisms responsible for polarization control of air-plasma-based terahertz sources.
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Affiliation(s)
- Xiaofei Lu
- Department of Physics, Applied Physics, and Astronomy, Center for Terahertz Research, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
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59
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Fu LB, Xin GG, Ye DF, Liu J. Recollision dynamics and phase diagram for nonsequential double ionization with circularly polarized laser fields. PHYSICAL REVIEW LETTERS 2012; 108:103601. [PMID: 22463407 DOI: 10.1103/physrevlett.108.103601] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Indexed: 05/31/2023]
Abstract
A semiclassical quasistatic model is used to investigate the recollision dynamics in circularly polarized laser fields. A velocity window for recollision to occur is found. Only when the return electron's orbits are irregular does significant double ionization take place. The model reproduces the experimental results for magnesium and explains the apparently conflicting experimental results in terms of an analytical formula that demarcates the phase diagram for the nonsequential double ionization in circularly polarized laser fields.
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Affiliation(s)
- L B Fu
- National Laboratory of Science and Technology on Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
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60
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Golubkov GV. Elementary processes involving Rydberg atoms and molecules in an intense laser radiation field. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2012. [DOI: 10.1134/s1990793111060078] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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61
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Wu J, Meckel M, Voss S, Sann H, Kunitski M, Schmidt LPH, Czasch A, Kim H, Jahnke T, Dörner R. Coulomb asymmetry in strong field multielectron ionization of diatomic molecules. PHYSICAL REVIEW LETTERS 2012; 108:043002. [PMID: 22400834 DOI: 10.1103/physrevlett.108.043002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Indexed: 05/31/2023]
Abstract
We measure the angular distribution of an electron emitted by a strong elliptically polarized two-color laser field from exploding doubly charged molecular nitrogen. This angular distribution is vastly different for emission of the electron from the up-field core of the molecule as compared to that from the down-field core. The emission from the down-field core leads to a slight rotation with respect to the internuclear axis in the direction expected by the Coulomb effect of the remaining ion, while, for the emission from the up-field core, this direction is inversed. Our semiclassical simulations suggest that this unexpected angular distribution is caused by an initial longitudinal momentum of the electron freed by over-the-barrier ionization above the inner barrier in the molecule. The initial kinetic energy is in the range of the potential energy of the Stark-shifted orbital above the barrier.
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Affiliation(s)
- J Wu
- Institut für Kernphysik, Goethe Universität, Max-von-Laue-Strasse 1, D-60438 Frankfurt, Germany
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62
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Odenweller M, Takemoto N, Vredenborg A, Cole K, Pahl K, Titze J, Schmidt LPH, Jahnke T, Dörner R, Becker A. Strong field electron emission from fixed in space H(2)(+) ions. PHYSICAL REVIEW LETTERS 2011; 107:143004. [PMID: 22107190 DOI: 10.1103/physrevlett.107.143004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Indexed: 05/31/2023]
Abstract
We have studied electron emission from the H(2)(+) ion by a circularly polarized laser pulse (800 nm, 6×10(14) W/cm(2)). The electron momentum distribution in the body fixed frame of the molecule is experimentally obtained by a coincident detection of electrons and protons. The data are compared to a solution of the time-dependent Schrödinger equation in two dimensions. We find radial and angular distributions which are at odds with the quasistatic enhanced ionization model. The unexpected momentum distribution is traced back to a complex laser-driven electron dynamics inside the molecule influencing the instant of ionization and the initial momentum of the electron.
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Affiliation(s)
- M Odenweller
- Institut für Kernphysik, J. W. Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt am Main, Germany
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63
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Smeenk CTL, Arissian L, Zhou B, Mysyrowicz A, Villeneuve DM, Staudte A, Corkum PB. Partitioning of the linear photon momentum in multiphoton ionization. PHYSICAL REVIEW LETTERS 2011; 106:193002. [PMID: 21668148 DOI: 10.1103/physrevlett.106.193002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Indexed: 05/30/2023]
Abstract
The balance of the linear photon momentum in multiphoton ionization is studied experimentally. In the experiment argon and neon atoms are singly ionized by circularly polarized laser pulses with a wavelength of 800 and 1400 nm in the intensity range of 10(14)-10(15) W/cm2. The photoelectrons are measured using velocity map imaging. We find that the photoelectrons carry linear momentum corresponding to the photons absorbed above the field free ionization threshold. Our finding has implications for concurrent models of the generation of terahertz radiation in filaments.
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Affiliation(s)
- C T L Smeenk
- JASLab, University of Ottawa and National Research Council, 100 Sussex Drive, Ottawa, Canada
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64
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Smeenk C, Salvail JZ, Arissian L, Corkum PB, Hebeisen CT, Staudte A. Precise in-situ measurement of laser pulse intensity using strong field ionization. OPTICS EXPRESS 2011; 19:9336-9344. [PMID: 21643189 DOI: 10.1364/oe.19.009336] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Building on the work of Alnaser et al. [Phys. Rev. A 70, 023413 (2004)], we devise an improved method for an in-situ measurement of the peak intensity in a focused, femtosecond infrared laser pulse. The method is shown to be effective with both photoion and photoelectron imaging devices. The model used to fit the experimental data has no unphysical free parameters used in fitting. The accuracy of the fit is 4% and the overall accuracy of the measurement is 8%.
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Affiliation(s)
- C Smeenk
- Joint Laboratory for Attosecond Science, University of Ottawa and National Research Council, 100 Sussex Drive, Ottawa, Canada.
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65
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Hansen JL, Stapelfeldt H, Dimitrovski D, Abu-samha M, Martiny CPJ, Madsen LB. Time-resolved photoelectron angular distributions from strong-field ionization of rotating naphthalene molecules. PHYSICAL REVIEW LETTERS 2011; 106:073001. [PMID: 21405510 DOI: 10.1103/physrevlett.106.073001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Indexed: 05/30/2023]
Abstract
A nanosecond laser pulse confines the spatial orientation of naphthalene in 1D or 3D while a femtosecond kick pulse initiates rotation of the molecular plane around the fixed long axis. Time-dependent photoelectron angular distributions (PADs), resulting from ionization by an intense femtosecond probe pulse, exhibit pronounced changes as the molecular plane rotates. Enhanced 3D alignment, occurring shortly after the kick pulse, provides strongly improved contrast in molecular-frame PADs. Calculations in the strong-field approximation show that the striking structures observed in the PADs originate from nodal planes in occupied valence orbitals.
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Affiliation(s)
- Jonas L Hansen
- Interdisciplinary Nanoscience Center, iNANO, Aarhus University, Denmark
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66
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Overstreet KR, Jones RR, Gallagher TF. Phase-dependent electron-ion recombination in a microwave field. PHYSICAL REVIEW LETTERS 2011; 106:033002. [PMID: 21405270 DOI: 10.1103/physrevlett.106.033002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Indexed: 05/30/2023]
Abstract
Using picosecond laser photoionization of Li in a microwave field we have observed phase-dependent reccombination of the photoelectrons with their parent Li+ ions. Recombination occurs at phases of the microwave field such that energy is removed from the photoelectron in the first microwave cycle after excitation, and there are two maxima in the recombination in each microwave cycle. These observations are consistent with observations made using an attosecond pulse train phase locked to an infrared pulse and with the "simpleman's" model, modified to account for the fact that the photoelectrons are produced in a Coulomb potential.
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Affiliation(s)
- K R Overstreet
- Department of Physics, University of Virginia, Charlottesville, Virginia 22904-4714, USA
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67
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Arabi AA, Matta CF. Effects of external electric fields on double proton transfer kinetics in the formic acid dimer. Phys Chem Chem Phys 2011; 13:13738-48. [DOI: 10.1039/c1cp20175a] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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68
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Talaat H, Sedik EWS, Kamal MTED. Laser Control of Ion/Atom–Molecule Interaction: Application to (X + CH 4, X = Li +and Li) Reactions. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2010. [DOI: 10.1246/bcsj.20090114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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69
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Reiss HR. Foundations of Strong-Field Physics. LECTURES ON ULTRAFAST INTENSE LASER SCIENCE 1 2010. [DOI: 10.1007/978-3-540-95944-1_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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70
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El-Din Kamal MT, Sedik EWS, Talaat H. Laser Induced Potential Energy Surface Crossing in Ion-Molecule Reactions: Application to Li++CH4. Z PHYS CHEM 2009. [DOI: 10.1524/zpch.2008.5435] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Laser ion-molecule reaction interaction through long range dipole moments leads to potential energy surface crossings. We will show here by using gauge representation (electric field gauge) for wave length λ = 20.6 μm, Intensity I = 5×1012 W/cm2, I = 1×1013 W/cm2, I = 3×1013 W/cm2, that we can create laser induced potential energy surface crossing in the virtual transition state region (4.a.u.) where the dipole moment changes sign. We illustrate such effects for the Li H + CH3
+ ↔ Li+ + CH4 reaction which takes the form of inverted Morse (without a barrier) using ab-initio methods for calculating the reaction path and the permanent dipole moment of this ion-molecule reaction.
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71
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Akagi H, Otobe T, Staudte A, Shiner A, Turner F, Dorner R, Villeneuve DM, Corkum PB. Laser Tunnel Ionization from Multiple Orbitals in HCl. Science 2009; 325:1364-7. [DOI: 10.1126/science.1175253] [Citation(s) in RCA: 259] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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72
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Quan W, Lin Z, Wu M, Kang H, Liu H, Liu X, Chen J, Liu J, He XT, Chen SG, Xiong H, Guo L, Xu H, Fu Y, Cheng Y, Xu ZZ. Classical aspects in above-threshold ionization with a midinfrared strong laser field. PHYSICAL REVIEW LETTERS 2009; 103:093001. [PMID: 19792794 DOI: 10.1103/physrevlett.103.093001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 03/26/2009] [Indexed: 05/28/2023]
Abstract
We present high resolution photoelectron energy spectra of noble gas atoms from high intensity above-threshold ionization (ATI) at midinfrared wavelengths. An unexpected structure at the very low-energy portion of the spectra, in striking contrast to the prediction of the simple-man theory, has been revealed. A semiclassical model calculation is able to reproduce the experimental feature and suggests the prominent role of the Coulomb interaction of the outgoing electron with the parent ion in producing the peculiar structure in long wavelength ATI spectra.
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Affiliation(s)
- W Quan
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
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73
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Bystrov AM, Gildenburg VB. Infrared to ultraviolet light conversion in laser-cluster interactions. PHYSICAL REVIEW LETTERS 2009; 103:083401. [PMID: 19792727 DOI: 10.1103/physrevlett.103.083401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Indexed: 05/28/2023]
Abstract
Spectrum conversion phenomena accompanying ionization of atomic clusters by few-cycle laser pulses are studied with the free (natural) plasma oscillations taken into account. These oscillations are found to be excited at the pulse leading front and to persist after passage of the pulse through the cluster, thus increasing the energy deposition to the plasma and affecting dramatically the scattered radiation spectrum: the Xe cluster irradiated by the near-infrared (800 nm) single-cycle pulse reradiates as a source of the ultraviolet light (360 nm).
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Affiliation(s)
- A M Bystrov
- Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia
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74
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Centurion M, Reckenthaeler P, Krausz F, Fill EE. Picosecond imaging of low-density plasmas by electron deflectometry. OPTICS LETTERS 2009; 34:539-541. [PMID: 19373367 DOI: 10.1364/ol.34.000539] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We have imaged optical-field ionized plasmas with electron densities as low as 10(13) cm(-3) on a picosecond timescale using ultrashort electron pulses. Electric fields generated by the separation of charges are imprinted on a 20 keV probe electron pulse and reveal a cloud of electrons expanding away from a positively charged plasma core. Our method allows for a direct measurement of the electron energy required to escape the plasma and the total charge. Simulations reproduce the main features of the experiment and allow determination of the energy of the electrons.
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Affiliation(s)
- M Centurion
- Max-Planck-Institut für Quantenoptik, D-85748 Garching, Germany.
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75
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Multiply ionization of benzene clusters by a nanosecond laser: Distributions of the ion charge state and the electron energy. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2008.12.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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76
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Staudte A, Patchkovskii S, Pavicić D, Akagi H, Smirnova O, Zeidler D, Meckel M, Villeneuve DM, Dörner R, Ivanov MY, Corkum PB. Angular tunneling ionization probability of fixed-in-space H2 molecules in intense laser pulses. PHYSICAL REVIEW LETTERS 2009; 102:033004. [PMID: 19257351 DOI: 10.1103/physrevlett.102.033004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2008] [Indexed: 05/27/2023]
Abstract
We propose a new approach to obtain molecular frame photoelectron angular distributions from molecules ionized by intense laser pulses. With our method we study the angular tunnel ionization probability of H2 at a wavelength of 800 nm over an intensity range of 2-4.5 x 10(14) W/cm2. We find an anisotropy that is stronger than predicted by any existing model. To explain the observed anisotropy and its strong intensity dependence we develop an analytical model in the framework of the strong-field approximation. It expresses molecular ionization as a product of atomic ionization rate and a Fourier transform of the highest occupied molecular orbital filtered by the strong-field ionization process.
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Affiliation(s)
- A Staudte
- National Research Council, 100 Sussex Drive, Ottawa, Ontario, Canada K1A 0R6
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77
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Shuman ES, Jones RR, Gallagher TF. Multiphoton assisted recombination. PHYSICAL REVIEW LETTERS 2008; 101:263001. [PMID: 19437638 DOI: 10.1103/physrevlett.101.263001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We have observed multiphoton assisted recombination in the presence of a 38.8 GHz microwave field. Stimulated emission of up to ten microwave photons results in energy transfer from continuum electrons, enabling recombination. The maximum electron energy loss is far greater than the 2Up predicted by the standard "simpleman's" model. The data are well reproduced by both an approximate analytic expression and numerical simulations in which the combined Coulomb and radiation fields are taken into account.
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Affiliation(s)
- E S Shuman
- Department of Physics, University of Virginia, Charlottesville, Virginia 22904-4714, USA
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78
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DiChiara AD, Ghebregziabher I, Sauer R, Waesche J, Palaniyappan S, Wen BL, Walker BC. Relativistic MeV photoelectrons from the single atom response of argon to a 10 19 W/cm2 laser field. PHYSICAL REVIEW LETTERS 2008; 101:173002. [PMID: 18999745 DOI: 10.1103/physrevlett.101.173002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Indexed: 05/27/2023]
Abstract
We present photoelectron measurements from argon ionization at 10(19) W/cm(2). Photoelectrons with energies above 400 keV, including a 1.2 MeV cutoff, are in quantitative agreement with a semiclassical, relativistic 3D ionization model that includes a nonparaxial laser field. L-shell photoelectrons have energies and momentum dominated by the field, including the acceleration out of the focus. Yields and angular distributions at 60 keV come from valence shell ionization by strong fields where rescattering and atomic processes determine photoelectron final states.
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Affiliation(s)
- A D DiChiara
- Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, USA
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79
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Loh ZH, Leone SR. Ultrafast strong-field dissociative ionization dynamics of CH2Br2 probed by femtosecond soft x-ray transient absorption spectroscopy. J Chem Phys 2008; 128:204302. [DOI: 10.1063/1.2925268] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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80
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Saalmann U, Rost JM. Rescattering for extended atomic systems. PHYSICAL REVIEW LETTERS 2008; 100:133006. [PMID: 18517947 DOI: 10.1103/physrevlett.100.133006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2007] [Indexed: 05/26/2023]
Abstract
Laser-driven rescattering of electrons is the basis of many strong-field phenomena in atoms and molecules. Here, we will show how this mechanism operates in extended atomic systems, giving rise to effective energy absorption. Rescattering from extended systems can also lead to energy loss, which in its extreme form results in nonlinear light-induced trapping. Intense-laser interaction with atomic clusters is discussed as an example. We explain fast electron emission, seen in experimental and numerically obtained spectra, by rescattering of electrons at the highly charged cluster.
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Affiliation(s)
- Ulf Saalmann
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Strasse 38, 01187 Dresden, Germany
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81
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Lewenstein M, L’Huillier A. Principles of Single Atom Physics: High-Order Harmonic Generation, Above-Threshold Ionization and Non-Sequential Ionization. STRONG FIELD LASER PHYSICS 2008. [DOI: 10.1007/978-0-387-34755-4_7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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82
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Luther-Davies B, Gamaliĭ EG, Wang Y, Rode AV, Tikhonchuk VT. Matter in ultrastrong laser fields. ACTA ACUST UNITED AC 2007. [DOI: 10.1070/qe1992v022n04abeh003433] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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83
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Okunishi M, Shimada K, Prümper G, Mathur D, Ueda K. Probing molecular symmetry effects in the ionization of N2 and O2 by intense laser fields. J Chem Phys 2007; 127:064310. [PMID: 17705599 DOI: 10.1063/1.2764029] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
High-resolution electron spectroscopy is used to explore the role played by molecular symmetry in determining the morphology of the energy spectra of electrons ejected when N2 and O2 are irradiated by intense laser fields. In O2, the low-energy part of the electron spectrum is curtailed due to the destructive interference brought about by the antibonding nature of the O2 valence orbital. The high-energy tail of the spectrum is also suppressed by virtue of electron rescattering being of little consequence in O2. In contrast, in N2, which has a bonding valence orbital, the electron dynamics follow the pattern that has been established for atomic ionization in strong optical fields.
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Affiliation(s)
- M Okunishi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan
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84
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Gildenburg VB, Vvedenskii NV. Optical-to-THz wave conversion via excitation of plasma oscillations in the tunneling-ionization process. PHYSICAL REVIEW LETTERS 2007; 98:245002. [PMID: 17677971 DOI: 10.1103/physrevlett.98.245002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2007] [Indexed: 05/16/2023]
Abstract
A new ("linear-parametric") mechanism of a direct conversion of an ultrashort laser pulse into terahertz radiation is suggested. The conversion is due to the ionization-induced excitation and the subsequent electromagnetic emission of the superluminous polarization wave created by the axicon-focused laser pulse. For a few-cycle pulse with an optimum carrier-envelope phase, the considered mechanism is found to be much more effective than the alternative one based on the excitation of plasma oscillations in the laser wakefield by the ponderomotive force and able to provide THz radiation of the gigawatt power level with the use of moderate optical intensity (approximately 10(14)-10(15) W/cm2).
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Affiliation(s)
- V B Gildenburg
- Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia
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85
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Loh ZH, Khalil M, Correa RE, Santra R, Buth C, Leone SR. Quantum state-resolved probing of strong-field-ionized xenon atoms using femtosecond high-order harmonic transient absorption spectroscopy. PHYSICAL REVIEW LETTERS 2007; 98:143601. [PMID: 17501273 DOI: 10.1103/physrevlett.98.143601] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Indexed: 05/15/2023]
Abstract
Femtosecond high-order harmonic transient absorption spectroscopy is used to resolve the complete |j,m quantum state distribution of Xe+ produced by optical strong-field ionization of Xe atoms at 800 nm. Probing at the Xe N4/5 edge yields a population distribution rhoj,|m| of rho3/2,1/2ratiorho1/2,1/2ratiorho3/2,3/2=75+/-6 :12+/-3 :13+/-6%. The result is compared to a tunnel ionization calculation with the inclusion of spin-orbit coupling, revealing nonadiabatic ionization behavior. The sub-50-fs time resolution paves the way for tabletop extreme ultraviolet absorption probing of ultrafast dynamics.
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Affiliation(s)
- Zhi-Heng Loh
- Department of Chemistry and Physics, University of California, Berkeley, California 94720, USA
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86
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Young L, Dunford R, Hoehr C, Kanter E, Krässig B, Peterson E, Southworth S, Ederer D, Rudati J, Arms D, Dufresne E, Landahl E. X-ray microprobe of optical strong-field processes. Radiat Phys Chem Oxf Engl 1993 2006. [DOI: 10.1016/j.radphyschem.2005.12.049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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87
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Barth I, Manz J, Shigeta Y, Yagi K. Unidirectional Electronic Ring Current Driven by a Few Cycle Circularly Polarized Laser Pulse: Quantum Model Simulations for Mg−Porphyrin. J Am Chem Soc 2006; 128:7043-9. [PMID: 16719485 DOI: 10.1021/ja057197l] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A circularly polarized ultraviolet (UV) laser pulse may excite a unidirectional valence-type electronic ring current in an oriented molecule, within the pulse duration of a few femtoseconds (e.g., tau = 3.5 fs). The mechanism is demonstrated by quantum model simulation for |X = |1(1)A(1g) --> |E(+) = |4 (1)E(u+) population transfer in the model system, Mg-porphyrin. The net ring current generated by the laser pulse (I = 84.5 microA) is at least 100 times stronger than any ring current, which could be induced by means of permanent magnetic fields, with present technology.
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Affiliation(s)
- Ingo Barth
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustrasse 3, 14195 Berlin, Germany
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88
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Arbó DG, Yoshida S, Persson E, Dimitriou KI, Burgdörfer J. Interference oscillations in the angular distribution of laser-ionized electrons near ionization threshold. PHYSICAL REVIEW LETTERS 2006; 96:143003. [PMID: 16712069 DOI: 10.1103/physrevlett.96.143003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2005] [Indexed: 05/09/2023]
Abstract
We analyze the two-dimensional momentum distribution of electrons ionized by few-cycle laser pulses in the transition regime from multiphoton absorption to tunneling by solving the time-dependent Schrödinger equation and by a classical-trajectory Monte-Carlo simulation with tunneling (CTMC-T). We find a complex two-dimensional interference pattern that resembles above threshold ionization (ATI) rings at higher energies and displays Ramsauer-Townsend-type diffraction oscillations in the angular distribution near threshold. CTMC-T calculations provide a semiclassical explanation for the dominance of selected partial waves. While the present calculation pertains to hydrogen, we find surprising qualitative agreement with recent experimental data for rare gases [A. Rudenko, J. Phys. B 37, L407 (2004)].
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Affiliation(s)
- D G Arbó
- Institute for Theoretical Physics, Vienna University of Technology, Wiedner Hauptstrasse 8-10/136, A-1040 Vienna, Austria, EU.
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89
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Parker JS, Doherty BJS, Taylor KT, Schultz KD, Blaga CI, DiMauro LF. High-energy cutoff in the spectrum of strong-field nonsequential double ionization. PHYSICAL REVIEW LETTERS 2006; 96:133001. [PMID: 16711984 DOI: 10.1103/physrevlett.96.133001] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Indexed: 05/09/2023]
Abstract
Electron energy distributions of singly and doubly ionized helium in an intense 390 nm laser field have been measured at two intensities (0.8 PW/cm2 and 1.1 PW/cm2, where PW is defined as 10(15) W/cm2). Numerical solutions of the full-dimensional time-dependent helium Schrödinger equation show excellent agreement with the experimental measurements. The high-energy portion of the two-electron energy distributions reveals an unexpected 5U(p) cutoff for the double ionization (DI) process and leads to a proposed model for DI below the quasiclassical threshold.
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Affiliation(s)
- J S Parker
- DAMTP, Queen's University Belfast, Belfast, BT7 1NN, United Kingdom
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90
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Stockman MI, Hewageegana P. Nanolocalized nonlinear electron photoemission under coherent control. NANO LETTERS 2005; 5:2325-9. [PMID: 16277477 DOI: 10.1021/nl051895m] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We theoretically show that two-photon coherent control yields electron photoemission from metal nanostructures that is localized in nanosize hot spots whose positions are controllable on a nanometer scale, in agreement with recent experiments. We propose to use silver V-shapes as tailored nanoantennas for which the position of the coherently controllable photoelectron emission hot spot can be deterministically predicted. We predict that the low-frequency, high-intensity (quasi-stationary) excitation of the photoemission leads to an exponentially high contrast of the coherent control.
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Affiliation(s)
- Mark I Stockman
- Department of Physics, Georgia State University, Atlanta, Georgia 30303, USA
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91
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He B, Chang TQ. Residual energy in optical-field-ionized plasmas with the longitudinal motion of electrons included. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 71:066411. [PMID: 16089884 DOI: 10.1103/physreve.71.066411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Indexed: 05/03/2023]
Abstract
The space-charge effect on the residual energy of electrons in optical-field-ionized plasmas is studied in detail by an extended simplified model and the cloud-in-cell simulation, with the longitudinal motion of electrons included. It is found that in moderate conditions the space-charge field can influence the residual energy of electrons effectively by matching the space-charge field with laser pulse. The effect of stimulated Raman scattering on electron temperature is also investigated in detail. Finally, a comparison is made between the results and experimental data.
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Affiliation(s)
- Bin He
- Institute of Applied Physics and Computational Mathematics P.O. Box 8009-57, Beijing 100088, People's Republic of China
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92
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Goreslavski SP, Paulus GG, Popruzhenko SV, Shvetsov-Shilovski NI. Coulomb asymmetry in above-threshold ionization. PHYSICAL REVIEW LETTERS 2004; 93:233002. [PMID: 15601154 DOI: 10.1103/physrevlett.93.233002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2004] [Indexed: 05/24/2023]
Abstract
A new method for including effects of the Coulomb potential in strong-field laser atom interaction is presented. The model is tested by comparing its results with experimental data of energy resolved angular distributions of photoelectrons. For elliptical polarization these exhibit a strong asymmetry. Our theory shows that this strong asymmetry for the low-energy electrons is induced by a small Coulomb force acting on the tunneling electron just after the exit of the tunnel. This is in contrast to the situation for high electron energies where the asymmetry arises via rescattering by the parent ion.
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Affiliation(s)
- S P Goreslavski
- Moscow State Engineering Physics Institute, Kashirskoe Shosse 31, 115409 Moscow, Russia
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93
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Chelkowski S, Bandrauk AD, Corkum PB. Muonic molecules in superintense laser fields. PHYSICAL REVIEW LETTERS 2004; 93:083602. [PMID: 15447184 DOI: 10.1103/physrevlett.93.083602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2003] [Indexed: 05/24/2023]
Abstract
We study theoretically the ionization and dissociation of muonic molecular ions (e.g., dd mu) in superintense laser fields. We predict that the bond breaks by tunneling of the lightest ion through a bond-softened barrier at intensity I > or =10(21) W/cm(2). Ionization of the muonic atomic fragment occurs at much higher intensity I > or =6 x 10(22) W/cm(2). Since the field controls the ion trajectory after dissociation, it forces recollision of a approximately 10(5)-10(6) eV ion with the muonic atom. Recollision can trigger a nuclear reaction with sub-laser-cycle precision. In general, molecules can serve as precursors for laser control of nuclear processes.
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Affiliation(s)
- Szczepan Chelkowski
- Laboratoire de Chimie Théorique, Faculté des Sciences, Université de Sherbrooke, Québec J1K 2R1, Canada
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94
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Chen WT, Chien TY, Lee CH, Lin JY, Wang J, Chen SY. Optically controlled seeding of Raman forward scattering and injection of electrons in a self-modulated laser-wakefield accelerator. PHYSICAL REVIEW LETTERS 2004; 92:075003. [PMID: 14995864 DOI: 10.1103/physrevlett.92.075003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2003] [Indexed: 05/24/2023]
Abstract
Optical seeding of plasma waves and the injection of electrons are key issues in self-modulated laser-wakefield accelerators. By implementing a copropagating laser prepulse with proper timing, we are able to control the growth of Raman forward scattering and the production of accelerated electrons. The dependence of the Raman intensity on prepulse timing indicates that the seeding of Raman forward scattering is dominated by the ionization-induced wakefield, and the dependence of the divergence and number of accelerated electrons further reveals that the stimulated Raman backward scattering of the prepulse plays the essential role of injecting hot electrons into the fast plasma wave driven by the main pulse.
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Affiliation(s)
- W-T Chen
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
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95
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Bandrauk AD, Sedik EWS, Matta CF. Effect of absolute laser phase on reaction paths in laser-induced chemical reactions. J Chem Phys 2004; 121:7764-75. [PMID: 15485238 DOI: 10.1063/1.1793931] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Potential surfaces, dipole moments, and polarizabilities are calculated by ab initio methods [unrestricted MP2(full)/6-311++G(2d,2p)] along the reaction paths of the F+CH4 and Cl+CH4 reaction systems. It is found that in general dipole moments and polarizabilities exhibit peaks near the transition state. In the case of X=F these peaks are on the products side and in the case of X=Cl they are on the reactants side indicating an early transition state in the case of fluorine and a late transition state in the case of chlorine. An analysis of the geometric changes along the reaction paths reveals a one-to-one correspondence between the peaks in the electric properties and peaks in the rate of change of certain internal geometric coordinates along the reaction path. Interaction with short infrared intense laser fields pulses leads to the possibility of interferences between the dipole and polarizability laser-molecule interactions as a function of laser phase. The larger dipole moment in the Cl+CH4 reaction can lead to the creation of deep wells (instead of energy barriers) and new strongly bound states in the transition state region. This suggests possible coherent control of the reaction path as a function of the absolute phase of the incident field, by significant modification of the potential surfaces along the reaction path and, in particular, in the transition state region.
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Affiliation(s)
- André D Bandrauk
- Laboratoire de Chimie Theorique, Faculté des Sciences, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1, Canada.
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96
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Popov VS. Tunnel and multiphoton ionization of atoms and ions in a strong laser field (Keldysh theory). ACTA ACUST UNITED AC 2004. [DOI: 10.3367/ufnr.0174.200409a.0921] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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97
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Rajgara FA, Krishnamurthy M, Mathur D. Electron rescattering and the dissociative ionization of alcohols in intense laser light. J Chem Phys 2003. [DOI: 10.1063/1.1625637] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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98
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Krainov VP. Generation of high-order harmonics in plasmas of multicharged atomic ions produced by an intense laser pulse. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2003; 68:027401. [PMID: 14525155 DOI: 10.1103/physreve.68.027401] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2003] [Indexed: 11/07/2022]
Abstract
The yield of high-order harmonics has been derived for relativistic plasmas of multicharged atomic ions produced by an intense, linearly polarized laser pulse. Harmonics of the laser field are excited at the elastic electron-ion collisions in plasmas. In the nonrelativistic case only odd harmonics can be excited. The ultrarelativistic limit is considered when both even and odd harmonics are excited with the comparable efficiencies. Drift electron velocities are assumed to be small compared to the quiver electron velocities. It is shown that the harmonic yields do not depend on the instantaneous energy distribution of electrons produced at the multiple ionization on the leading edge of the laser pulse. The harmonic conductivity is a tensor with odd components along the laser polarization and with even components along the direction of propagation of the laser pulse. This conductivity tensor has been derived analytically in the ultrarelativistic limit. Possible observation of even harmonics is discussed with respect to the Weibel effect in laser plasmas.
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Affiliation(s)
- V P Krainov
- Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Moscow Region, Russia
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99
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Moshammer R, Ullrich J, Feuerstein B, Fischer D, Dorn A, Schröter CD, Crespo Lopez-Urrutia JR, Hoehr C, Rottke H, Trump C, Wittmann M, Korn G, Sandner W. Rescattering of ultralow-energy electrons for single ionization of Ne in the tunneling regime. PHYSICAL REVIEW LETTERS 2003; 91:113002. [PMID: 14525419 DOI: 10.1103/physrevlett.91.113002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2003] [Indexed: 05/24/2023]
Abstract
Electron emission for single ionization of Ne by 25 fs, 1.0 PW/cm(2) laser pulses at 800 nm has been investigated in a kinematically complete experiment using a "reaction microscope." Mapping the complete final state momentum space with high resolution, a distinct local minimum is observed at P(e parallel )=0, where P(e parallel ) is the electron momentum parallel to the laser polarization. Whereas tunneling theory predicts a maximum at zero momentum, our findings are in good agreement with recent semiclassical predictions which were interpreted to be due to "recollision."
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Affiliation(s)
- R Moshammer
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-67119 Heidelberg, Germany.
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100
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Ferrante G, Zarcone M, Uryupin SA. Anomalous transmission of an ultrashort ionizing laser pulse through a thin foil. PHYSICAL REVIEW LETTERS 2003; 91:085005. [PMID: 14525249 DOI: 10.1103/physrevlett.91.085005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2002] [Indexed: 05/24/2023]
Abstract
The formation of a highly anisotropic photoelectron velocity distribution as a result of the interaction of a powerful ultrashort laser pulse with a thin foil is found to yield a large skin-layer depth and an anomalous increase of the transmission coefficient. The physical reason for the effect is the influence of the incident wave magnetic field, through the Lorenz force, on the electron kinetics in the skin layer.
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Affiliation(s)
- G Ferrante
- Istituto Nazionale per la Fisica della Materia and Dipartimento di Fisica e Tecnologie Relative, Viale delle Scienze, 90128 Palermo, Italy
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