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 Photodetachment (2)
 Bremsstrahlung (1)
 Highorder harmonic generation (1)
 Elliptical polarization (1)
 Atomic and molecular physics (1)

 Laserassisted (1)
 Green’s functions (1)
 Imaging electronic motion (1)
 Diatomic molecule (1)
 Photoelectron angular distribution (1)
 Circularlypolarized attosecond pulses (1)
 Entanglement in spin models (1)
 Autoionization (1)
 Multipath ionization interferometry (1)
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 Doublyexcited state dynamics (1)
 Excitation (1)
 Multiphoton ionization (1)
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 Auger effect (1)
 Excited atom or ion (1)
 Electron–atom (1)
 Electron matterwave vortices (1)
 Adiabatic passage (1)
 Partial cross section (1)
 He atom (1)
 Entanglement in quantum phase transitions (1)
 Circular dichroism (1)
Articles 1  30 of 223
FullText Articles in Physics
Performance Of Plastic Electron Optics Components Fabricated Using A 3d Printer, Phillip Wiebe, Peter Beierle, HuaChieh Shao, Bret Gergely, Anthony F. Starace, Herman Batelaan
Performance Of Plastic Electron Optics Components Fabricated Using A 3d Printer, Phillip Wiebe, Peter Beierle, HuaChieh Shao, Bret Gergely, Anthony F. Starace, Herman Batelaan
Anthony F. Starace Publications
We show images produced by an electron beam deflector, a quadrupole lens and a einzel lens fabricated from conducting and nonconducting plastic using a 3D printer. Despite the difficulties associated with the use of plastics in vacuum, such as outgassing, poor conductivity, and print defects, the devices were used successfully in vacuum to steer, stretch and focus electron beams to millimeter diameters. Simulations indicate that much smaller focus spot sizes might be possible for such 3Dprinted plastic electron lenses taking into account some possible surface defects. This work was motivated by our need to place electron optical components in difficulttoaccess ...
Analytic Generalized Description Of A Perturbative Nonparaxial Elegant LaguerreGaussian Phasor For Ultrashort Pulses In The Time Domain, Andrew Vikartofsky, Ethan C. Jahns, Anthony F. Starace
Analytic Generalized Description Of A Perturbative Nonparaxial Elegant LaguerreGaussian Phasor For Ultrashort Pulses In The Time Domain, Andrew Vikartofsky, Ethan C. Jahns, Anthony F. Starace
Anthony F. Starace Publications
An analytic expression for a polychromatic phasor representing an arbitrarily short elegant LaguerreGauss (eLG) laser pulse of any spot size and LG mode is presented in the time domain as a nonrecursive, closedform perturbative expansion valid to any order of perturbative correction. This phasor enables the calculation of the complex electromagnetic fields for such beams without requiring the evaluation of any Fourier integrals. It is thus straightforward to implement in analytical or numerical applications involving eLG pulses.
Analytic Description Of HighOrder Harmonic Generation In The Adiabatic Limit With Application To An Initial S State In An Intense Bicircular Laser Pulse, M. V. Frolov, N. L. Manakov, A. A. Minina, A. A. Silaev, N. V. Vvedenskii, M. Yu. Ivanov, Anthony F. Starace
Analytic Description Of HighOrder Harmonic Generation In The Adiabatic Limit With Application To An Initial S State In An Intense Bicircular Laser Pulse, M. V. Frolov, N. L. Manakov, A. A. Minina, A. A. Silaev, N. V. Vvedenskii, M. Yu. Ivanov, Anthony F. Starace
Anthony F. Starace Publications
An analytic description of highorder harmonic generation (HHG) is proposed in the adiabatic (lowfrequency) limit for an initial s state and a laser field having an arbitrary wave form. The approach is based on the twostate timedependent effective range theory and is extended to the case of neutral atoms and positively charged ions by introducing ad hoc the Coulomb corrections for HHG. The resulting closed analytical form for the HHG amplitude is discussed in terms of real classical trajectories. The accuracy of the results of our analytic model is demonstrated by comparison with numerical solutions of the timedependent Schrödinger equation ...
Violation Of Centrosymmetry In TimeResolved Coherent XRay Diffraction From Rovibrational States Of Diatomic Molecules, HuaChieh Shao, Anthony F. Starace
Violation Of Centrosymmetry In TimeResolved Coherent XRay Diffraction From Rovibrational States Of Diatomic Molecules, HuaChieh Shao, Anthony F. Starace
Anthony F. Starace Publications
Owing to increasing applications of timeresolved coherent xray scattering for the investigation of molecular reaction dynamics, we develop a theoretical model for timedependent xray diffraction from molecular and/or electronic motion in molecules. Our model shows that the violation of centrosymmetry (VOC) is a general phenomenon in timeresolved diffraction patterns. We employ our theoretical model to illustrate the VOC in timeresolved coherent xray diffraction from two oriented diatomic molecules undergoing rovibrational motion: lithium hydride (LiD) and hydrogen (HD). Our simulations show asymmetric xray diffraction images that reflect the directions of the molecular motions.
Dynamical Electron Vortices In Attosecond Double Photoionization Of H_{2}, Jean Marcel Ngoko Djiokap, A. V. Meremianin, N. L. Manakov, L. B. Madsen, S. X. Hu, Anthony F. Starace
Dynamical Electron Vortices In Attosecond Double Photoionization Of H2, Jean Marcel Ngoko Djiokap, A. V. Meremianin, N. L. Manakov, L. B. Madsen, S. X. Hu, Anthony F. Starace
Anthony F. Starace Publications
We study electron momentum vortices in singlephoton double ionization of H2 by timedelayed, counterrotating, elliptically polarized attosecond pulses propagating along kˆ either parallel or perpendicular to the molecular axis R. For kˆ  R, kinematical vortices occur similar to those found for He. For kˆ ⊥ R, we find dynamical vortex structures originating from an ellipticitydependent interplay of ^{1}∑^{+}_{u} and ^{1}∏^{+}_{u} continuum amplitudes. We propose a complete experiment to determine the magnitudes and relative phase of these amplitudes by varying pulse ellipticities and time delays.
Perturbative Representation Of Ultrashort Nonparaxial Elegant LaguerreGaussian Fields, Andrew Vikartofsky, Anthony F. Starace, LiangWen Pi
Perturbative Representation Of Ultrashort Nonparaxial Elegant LaguerreGaussian Fields, Andrew Vikartofsky, Anthony F. Starace, LiangWen Pi
Anthony F. Starace Publications
An analytical method for calculating the electromagnetic fields of a nonparaxial elegant LaguerreGaussian (LG) vortex beam is presented for arbitrary pulse duration, spot size, and LG mode. This perturbative approach provides a numerically tractable model for the calculation of arbitrarily high radial and azimuthal LG modes in the nonparaxial regime, without requiring integral representations of the fields. A key feature of this perturbative model is its use of a Poissonlike frequency spectrum, which allows for the proper description of pulses of arbitrarily short duration. This model is thus appropriate for simulating lasermatter interactions, including those involving short laser pulses.
Control Of Harmonic Generation By The Time Delay Between TwoColor, Bicircular FewCycle MidIr Laser Pulses, M. V. Frolov, N. L. Manakov, A. A. Minina, N. V. Vvedenskii, A. A. Silaev, M. Yu. Ivanov, Anthony F. Starace
Control Of Harmonic Generation By The Time Delay Between TwoColor, Bicircular FewCycle MidIr Laser Pulses, M. V. Frolov, N. L. Manakov, A. A. Minina, N. V. Vvedenskii, A. A. Silaev, M. Yu. Ivanov, Anthony F. Starace
Anthony F. Starace Publications
We study control of highorder harmonic generation (HHG) driven by timedelayed, fewcycle ω and 2ω counterrotating midIR pulses. Our numerical and analytical study shows that the time delay between the twocolor pulses allows control of the harmonic positions, both those allowed by angular momentum conservation and those seemingly forbidden by it. Moreover, the helicity of any particular harmonic is tunable from left to right circular without changing the driving pulse helicity. The highest HHG yield occurs for a time delay comparable to the fundamental period T = 2π/ω.
Enhancing HighOrder Harmonic Generation By Sculpting Waveforms With Chirp, Dian Peng, M. V. Frolov, LiangWen Pi, Anthony F. Starace
Enhancing HighOrder Harmonic Generation By Sculpting Waveforms With Chirp, Dian Peng, M. V. Frolov, LiangWen Pi, Anthony F. Starace
Anthony F. Starace Publications
We present a theoretical analysis showing how chirp can be used to sculpt twocolor driving laser field waveforms in order to enhance highorder harmonic generation (HHG) and/or extend HHG cutoff energies. Specifically, we consider driving laser field waveforms composed of two ultrashort pulses having different carrier frequencies in each of which a linear chirp is introduced. Two pairs of carrier frequencies of the component pulses are considered: (ω, 2ω) and (ω, 3ω). Our results show how changing the signs of the chirps in each of the two component pulses leads to drastic changes in the HHG spectra. Our theoretical ...
TimeResolved Electron (E,2E) Momentum Spectroscopy: Application To LaserDriven Electron Population Transfer In Atoms, HuaChieh Shao, Anthony F. Starace
TimeResolved Electron (E,2E) Momentum Spectroscopy: Application To LaserDriven Electron Population Transfer In Atoms, HuaChieh Shao, Anthony F. Starace
Anthony F. Starace Publications
Owing to its ability to provide unique information on electron dynamics, timeresolved electron momentum spectroscopy (EMS) is used to study theoretically a laserdriven electronic motion in atoms. Specifically, a chirped laser pulse is used to adiabatically transfer the populations of lithium atoms from the ground state to the first excited state. During this process, impact ionization near the Bethe ridge by timedelayed ultrashort, highenergy electron pulses is used to image the instantaneous momentum density of this electronic population transfer. Simulations with 100 fs and 1 fs pulse durations demonstrate the capability of EMS to image the timevarying momentum density, including ...
XuvAssisted HighOrderHarmonicGeneration Spectroscopy, T. S. Sarantseva, M. V. Frolov, N. L. Manakov, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace
XuvAssisted HighOrderHarmonicGeneration Spectroscopy, T. S. Sarantseva, M. V. Frolov, N. L. Manakov, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace
Anthony F. Starace Publications
Using the analytic timedependent effective range theory, we study twocolor highorder harmonic generation (HHG) involving a weak extreme ultraviolet (XUV) pulse and an intense infrared laser field. Our analysis shows that XUVassisted HHG spectra contain multiple additional plateau structures originating from absorption of one or more XUV photons at the photorecombination step of HHG. We show also that the HHG rate corresponding to the nth plateau can be presented in a factorized form involving the XUVassisted (multiphoton) photorecombination cross section (PRCS) corresponding to absorption of n XUV photons of energy Ω and emission of a harmonic of energy Ω_{h ...}
DoublyExcited State Effects On TwoPhoton Double Ionization Of Helium By TimeDelayed, Oppositely CircularlyPolarized Attosecond Pulses, Jean Marcel Ngoko Djiokap, Anthony F. Starace
DoublyExcited State Effects On TwoPhoton Double Ionization Of Helium By TimeDelayed, Oppositely CircularlyPolarized Attosecond Pulses, Jean Marcel Ngoko Djiokap, Anthony F. Starace
Anthony F. Starace Publications
We study twophoton double ionization (TPDI) of helium by a pair of timedelayed (nonoverlapping), oppositely circularlypolarized attosecond pulses whose carrier frequencies are resonant with ^{1}P^{o} doublyexcited states. All of our TPDI results are obtained by numerical solution of the twoelectron timedependent Schrödinger equation for the sixdimensional case of circularlypolarized attosecond pulses, and they are analyzed using perturbation theory (PT). As compared with the corresponding nonresonant TPDI process, we find that the doublyexcited states change the character of vortex patterns in the twoelectron momentum distributions for the case of backtoback detection of the two ionized electrons in the polarization ...
Imaging Electronic Motions By Ultrafast Electron Diffraction, HuaChieh Shao, Anthony F. Starace
Imaging Electronic Motions By Ultrafast Electron Diffraction, HuaChieh Shao, Anthony F. Starace
Anthony F. Starace Publications
Recently ultrafast electron diffraction and microscopy have reached unprecedented temporal resolution, and transient structures with atomic precision have been observed in various reactions. It is anticipated that these extraordinary advances will soon allow direct observation of electronic motions during chemical reactions. We therefore performed a series of theoretical investigations and simulations to investigate the imaging of electronic motions in atoms and molecules by ultrafast electron diffraction. Three prototypical electronic motions were considered for hydrogen atoms. For the case of a breathing mode, the electron density expands and contracts periodically, and we show that the timeresolved scattering intensities reflect such changes ...
EnergyResolved Coherent Diffraction From LaserDriven Electronic Motion In Atoms, HuaChieh Shao, Anthony F. Starace
EnergyResolved Coherent Diffraction From LaserDriven Electronic Motion In Atoms, HuaChieh Shao, Anthony F. Starace
Anthony F. Starace Publications
We investigate theoretically the use of energyresolved ultrafast electron diffraction to image laserdriven electronic motion in atoms. A chirped laser pulse is used to transfer the valence electron of the lithium atom from the ground state to the first excited state. During this process, the electronic motion is imaged by 100fs and 1fs electron pulses in energyresolved diffraction measurements. Simulations show that the angleresolved spectra reveal the time evolution of the energy content and symmetry of the electronic state. The timedependent diffraction patterns are further interpreted in terms of the momentum transfer. For the case of incident 1fs electron pulses ...
Ionization Enhancement And Suppression By PhaseLocked Ultrafast Pulse Pairs, David B. Foote, Y. Lin, LiangWen Pi, Jean Marcel Ngoko Djiokap, Anthony F. Starace, W. T. Hill
Ionization Enhancement And Suppression By PhaseLocked Ultrafast Pulse Pairs, David B. Foote, Y. Lin, LiangWen Pi, Jean Marcel Ngoko Djiokap, Anthony F. Starace, W. T. Hill
Anthony F. Starace Publications
We present the results of a study of ionization of Xe atoms by a pair of phaselocked pulses, which is characterized by interference produced by the twin peaks. Two types of interference are considered: ordinary optical interference, which changes the intensity of the composite pulse and thus the ion yield, and a quantum interference, in which the excited electron wave packets interfere. We use the measured Xe+ yield as a function of the temporal delay and/or relative phase between the peaks to monitor the interferences and compare their relative strengths. We model the interference with a pulse intensity function ...
AdiabaticLimit Coulomb Factors For Photoelectron And HighOrderHarmonic Spectra, M. V. Frolov, N. L. Manakov, A. A. Minina, S. V. Popruzhenko, Anthony F. Starace
AdiabaticLimit Coulomb Factors For Photoelectron And HighOrderHarmonic Spectra, M. V. Frolov, N. L. Manakov, A. A. Minina, S. V. Popruzhenko, Anthony F. Starace
Anthony F. Starace Publications
A momentumdependent Coulomb factor in the probability for nonlinear ionization of atoms by a strong lowfrequency laser field is calculated analytically in the adiabatic approximation. Expressions for this Coulomb factor, valid for an arbitrary laser pulse waveform, are obtained and analyzed in detail for the cases of linear and circular polarizations. The dependence of the Coulomb factor on the photoelectron momentum is shown to be significant in both cases. Using a similar technique, the Coulomb factor for emission of highorder harmonics by an atom in a bichromatic laser field is also calculated. In contrast to the case of a singlefrequency ...
Kinematical Vortices In Double Photoionization Of Helium By Attosecond Pulses, Jean Marcel Ngoko Djiokap, A. V. Meremianin, N. L. Manakov, S. X. Hu, L. B. Madsen, Anthony F. Starace
Kinematical Vortices In Double Photoionization Of Helium By Attosecond Pulses, Jean Marcel Ngoko Djiokap, A. V. Meremianin, N. L. Manakov, S. X. Hu, L. B. Madsen, Anthony F. Starace
Anthony F. Starace Publications
Twoarmed helical vortex structures are predicted in the twoelectron momentum distributions produced in double photoionization (DPI) of the He atom by a pair of timedelayed elliptically polarized attosecond pulses with opposite helicities. These predictions are based upon both a firstorder perturbation theory analysis and numerical solutions of the twoelectron, timedependent Schrödinger equation in six spatial dimensions. The helical vortex structures originate from Ramsey interference of a pair of ionized twoelectron wave packets, each having a total angular momentum of unity, and appear in the sixfold differential DPI probability distribution for any energy partitioning between the two electrons. The vortex structures ...
Discontinuities In The Electromagnetic Fields Of Vortex Beams In The Complex SourceSink Model, Andrew Vikartofsky, LiangWen Pi, Anthony F. Starace
Discontinuities In The Electromagnetic Fields Of Vortex Beams In The Complex SourceSink Model, Andrew Vikartofsky, LiangWen Pi, Anthony F. Starace
Anthony F. Starace Publications
An analytical discontinuity is reported in what was thought to be the discontinuityfree exact nonparaxial vortex beam phasor obtained within the complex sourcesink model. This discontinuity appears for all odd values of the orbital angular momentum mode. Such discontinuities in the phasor lead to nonphysical discontinuities in the real electromagnetic field components. We identify the source of the discontinuities, and provide graphical evidence of the discontinuous real electric fields for the first and third orbital angular momentum modes. A simple means of avoiding these discontinuities is presented.
Enhancing HighOrderHarmonic Generation By Time Delays Between TwoColor, FewCycle Pulses, Dian Peng, LiangWen Pi, M. V. Frolov, Anthony F. Starace
Enhancing HighOrderHarmonic Generation By Time Delays Between TwoColor, FewCycle Pulses, Dian Peng, LiangWen Pi, M. V. Frolov, Anthony F. Starace
Anthony F. Starace Publications
Use of time delays in highorderharmonic generation (HHG) driven by intense twocolor, fewcycle pulses is investigated in order to determine means of optimizing HHG intensities and plateau cutoff energies. Based upon numerical solutions of the timedependent Schrõdinger equation for the H atom as well as analytical analyses, we show that introducing a time delay between the twocolor, fewcycle pulses can result in an enhancement of the intensity of the HHG spectrum by an order of magnitude (or more) at the cost of a reduction in the HHG plateau cutoff energy. Results for both positive and negative time delays as well ...
Imaging Population Transfer In Atoms With Ultrafast Electron Pulses, HuaChieh Shao, Anthony F. Starace
Imaging Population Transfer In Atoms With Ultrafast Electron Pulses, HuaChieh Shao, Anthony F. Starace
Anthony F. Starace Publications
We propose the use of ultrafast electron diffraction (UED) to image a controllable, laserdriven coherent electron population transfer in lithium atoms with currently available femtosecond electron pulses. Our simulations demonstrate the ability of ultrafast electrons to image such an electronic population transfer, thus validating UED as a direct means of investigating electron dynamics. Provided the incident electron pulses have sufficient temporal resolution, the diffraction images are shown to resolve also the relative phases of the target electronic wave functions.
Multistart Spiral Electron Vortices In Ionization By Circularly Polarized Uv Pulses, Jean Marcel Ngoko Djiokap, Alexei V. Meremianin, N. L. Manakov, S. X. Hu, L. B. Madsen, Anthony F. Starace
Multistart Spiral Electron Vortices In Ionization By Circularly Polarized Uv Pulses, Jean Marcel Ngoko Djiokap, Alexei V. Meremianin, N. L. Manakov, S. X. Hu, L. B. Madsen, Anthony F. Starace
Anthony F. Starace Publications
Multistart spiral vortex patterns are predicted for the electron momentum distributions in the polarization plane following ionization of the helium atom by two timedelayed circularly polarized ultrashort laser pulses. For two ultraviolet (UV) pulses having the same frequency (such that two photons are required for ionization), singlecolor twophoton interferometry with corotating or counterrotating timedelayed pulses is found to lead respectively to zerostart or fourstart spiral vortex patterns in the ionized electron momentum distributions in the polarization plane. In contrast, twocolor onephoton plus twophoton interferometry with timedelayed corotating or counterrotating UV pulses is found to lead respectively to one ...
Atomic Photoionization Experiment By HarmonicGeneration Spectroscopy, M. V. Frolov, T. S. Sarantseva, N. L. Manakov, K. D. Fulfer, B. P. Wilson, J. Troß, X. Ren, Erwin D. Poliakoff, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace, C. A. TralleroHerrero
Atomic Photoionization Experiment By HarmonicGeneration Spectroscopy, M. V. Frolov, T. S. Sarantseva, N. L. Manakov, K. D. Fulfer, B. P. Wilson, J. Troß, X. Ren, Erwin D. Poliakoff, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace, C. A. TralleroHerrero
Anthony F. Starace Publications
Measurements of the highorderharmonic generation yield of the argon (Ar) atom driven by a strong elliptically polarized laser field are shown to completely determine the fieldfree differential photoionization cross section of Ar, i.e., the energy dependence of both the angleintegrated photoionization cross section and the angular distribution asymmetry parameter.
Control Of Threshold Enhancements In Harmonic Generation By Atoms In A TwoColor Laser Field With Orthogonal Polarizations, M. V. Frolov, N. L. Manakov, T. S. Sarantseva, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace
Control Of Threshold Enhancements In Harmonic Generation By Atoms In A TwoColor Laser Field With Orthogonal Polarizations, M. V. Frolov, N. L. Manakov, T. S. Sarantseva, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace
Anthony F. Starace Publications
Threshold phenomena (or channelclosing effects) are analyzed in highorder harmonic generation (HHG) by atoms in a twocolor laser field with orthogonal linearly polarized components of a fundamental field and its second harmonic. We show that the threshold behavior of HHG rates for the case of a weak second harmonic component is sensitive to the parity of a closing multiphoton ionization channel and the spatial symmetry of the initial bound state of the target atom, while for the case of comparable intensities of both components, suppression of threshold phenomena is observed as the relative phase between the components of a twocolor ...
Electron Vortices In Photoionization By Circularly Polarized Attosecond Pulses, Jean Marcel Ngoko Djiokap, S. X. Hu, L. B. Madsen, N. L. Manakov, A. V. Meremianin, Anthony F. Starace
Electron Vortices In Photoionization By Circularly Polarized Attosecond Pulses, Jean Marcel Ngoko Djiokap, S. X. Hu, L. B. Madsen, N. L. Manakov, A. V. Meremianin, Anthony F. Starace
Anthony F. Starace Publications
Single ionization of He by two oppositely circularly polarized, timedelayed attosecond pulses is shown to produce photoelectron momentum distributions in the polarization plane having helical vortex structures sensitive to the time delay between the pulses, their relative phase, and their handedness. Results are obtained by both ab initio numerical solution of the twoelectron timedependent Schrödinger equation and by a lowestorder perturbation theory analysis. The energy, bandwidth, and temporal duration of attosecond pulses are ideal for observing these vortex patterns.
Scaling Laws For HighOrderHarmonic Generation With Midinfrared Laser Pulses, M. V. Frolov, N. L. Manakov, WeiHao Xiong, LiangYou Peng, J. Burgdörfer, Anthony F. Starace
Scaling Laws For HighOrderHarmonic Generation With Midinfrared Laser Pulses, M. V. Frolov, N. L. Manakov, WeiHao Xiong, LiangYou Peng, J. Burgdörfer, Anthony F. Starace
Anthony F. Starace Publications
We derive an analytic expression for thewavelength scaling of the highorderharmonic generation (HHG) yield induced by midinfrared driving laser fields. It is based on a quasiclassical description of the returning electron wave packet, which is shown to be largely independent of atomic properties. The accuracy of this analytic expression is confirmed by comparison with results of numerical solutions of the timedependent Schr¨odinger equation for wavelengths in the range of 1.4 μm ≤ λ ≤ 4 μm. We verify the wavelength scaling of the HHG yield found numerically for midinfrared laser fields in a recent paper by Le et al. [
Favorable Target Positions For Intense Laser Acceleration Of Electrons In HydrogenLike, HighlyCharged Ions, LiangWen Pi, S. X. Hu, Anthony F. Starace
Favorable Target Positions For Intense Laser Acceleration Of Electrons In HydrogenLike, HighlyCharged Ions, LiangWen Pi, S. X. Hu, Anthony F. Starace
Anthony F. Starace Publications
Classical relativistic Monte Carlo simulations of petawatt laser acceleration of electrons bound initially in hydrogenlike, highlycharged ions show that both the angles and energies of the laseraccelerated electrons depend on the initial ion positions with respect to the laser focus. Electrons bound in ions located after the laser focus generally acquire higher (≈GeV) energies and are ejected at smaller angles with respect to the laser beam. Our simulations assume a tightlyfocused linearlypolarized laser pulse with intensity approaching 10^{22}W/cm^{2}. Up to fifth order corrections to the paraxial approximation of the laser field in the focal region are ...
Photodetachment Of A Model Molecular System By An Elliptically Polarized Field, M. V. Frolov, N. L. Manakov, S. S. Marmo, Anthony F. Starace
Photodetachment Of A Model Molecular System By An Elliptically Polarized Field, M. V. Frolov, N. L. Manakov, S. S. Marmo, Anthony F. Starace
Anthony F. Starace Publications
The differential cross section for onephoton molecular detachment by an elliptically polarized field is analyzed for a oneelectron molecular model comprised of an electron in the field of two (generally nonequivalent) attractive zerorange potentials (ZRPs) separated by the distance R. A phenomenological parametrization of the photodetachment cross section for a fixedinspace molecular system in terms of two scalar dynamical parameters is presented and circular dichroism effects are discussed. Analytic results for the dynamical molecular parameters within the ZRP molecular model are used to analyze interference phenomena (including twocenter interference) and dichroic effects in the detached electron angular distributions and their ...
Rescattering Effects In LaserAssisted ElectronAtom Bremsstrahlung, A. N. Zheltukhin, A. V. Flegel, M. V. Frolov, N. L. Manakov, Anthony F. Starace
Rescattering Effects In LaserAssisted ElectronAtom Bremsstrahlung, A. N. Zheltukhin, A. V. Flegel, M. V. Frolov, N. L. Manakov, Anthony F. Starace
Anthony F. Starace Publications
Rescattering effects in nonresonant spontaneous laserassisted electron–atom bremsstrahlung (LABrS) are analyzed within the framework of timedependent effectiverange (TDER) theory. It is shown that high energy LABrS spectra exhibit rescattering plateau structures that are similar to those that are wellknown in strong field laserinduced processes as well as those that have been predicted theoretically in laserassisted collision processes. In the limit of a lowfrequency laser field, an analytic description of LABrS is obtained from a rigorous quantum analysis of the exact TDER results for the LABrS amplitude. This amplitude is represented as a sum of factorized terms involving three factors ...
Comment On “Universality Of Returning Electron Wave Packet In HighOrder Harmonic Generation With Midinfrared Laser Pulses”, M. V. Frolov, N. L. Manakov, WeiHao Xiong, LiangYou Peng, J. Burgdörfer, Anthony F. Starace
Comment On “Universality Of Returning Electron Wave Packet In HighOrder Harmonic Generation With Midinfrared Laser Pulses”, M. V. Frolov, N. L. Manakov, WeiHao Xiong, LiangYou Peng, J. Burgdörfer, Anthony F. Starace
Anthony F. Starace Publications
In conclusion, we have shown that when the same definition for the HHG yield is used [cf. Eq. (1)], the results of Ref. [1] give the same scaling law found earlier in Refs. [2–5] for wavelengths λ ≤ 2 μm. We note that this latter scaling law can be obtained analytically by using results of the model developed in Ref. [6] for the description of shortpulse HHG spectra. These analytic results as well as new numerical TDSE results for longer wavelengths, λ ≤ 4 μm, will be published elsewhere.
Nonlinear Dichroism In BackToBack Double Ionization Of He By An Intense Elliptically Polarized FewCycle Extreme Ultraviolet Pulse, Jean Marcel Ngoko Djiokap, N. L. Manakov, A. V. Meremianin, S. X. Hu, L. B. Madsen, Anthony F. Starace
Nonlinear Dichroism In BackToBack Double Ionization Of He By An Intense Elliptically Polarized FewCycle Extreme Ultraviolet Pulse, Jean Marcel Ngoko Djiokap, N. L. Manakov, A. V. Meremianin, S. X. Hu, L. B. Madsen, Anthony F. Starace
Anthony F. Starace Publications
Control of double ionization of He by means of the polarization and carrierenvelope phase (CEP) of an intense, fewcycle extreme ultraviolet (XUV) pulse is demonstrated numerically by solving the sixdimensional twoelectron, timedependent Schrödinger equation for He interacting with an elliptically polarized XUV pulse. Guided by perturbation theory (PT), we predict the existence of a nonlinear dichroic effect (∝ I^{3/2}) that is sensitive to the CEP, ellipticity, peak intensity I, and temporal duration of the pulse. This dichroic effect (i.e., the difference of the twoelectron angular distributions for opposite helicities of the ionizing XUV pulse) originates from interference of ...
Resonant ElectronAtom Bremsstrahlung In An Intense Laser Field, A. N. Zheltukhin, A. V. Flegel, M. V. Frolov, N. L. Manakov, Anthony F. Starace
Resonant ElectronAtom Bremsstrahlung In An Intense Laser Field, A. N. Zheltukhin, A. V. Flegel, M. V. Frolov, N. L. Manakov, Anthony F. Starace
Anthony F. Starace Publications
We analyze a resonant mechanism for spontaneous laserassisted electron bremsstrahlung (BrS) involving the resonant transition (via either laserassisted electronion recombination or electronatom attachment) into a laserdressed intermediate quasibound state (corresponding, respectively, to either a fieldfree neutral atom or a negativeion bound state) accompanied by ionization or detachment of this state by the laser field. This mechanism leads to resonant enhancement (by orders of magnitude) of the BrS spectral density for emitted photon energies corresponding to those for laserassisted recombination or attachment. We present an accurate parametrization of the resonant BrS amplitude in terms of the amplitudes for nonresonant BrS, for ...