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Photodetachment Of He- In The Vicinity Of The He* (N=3, 4, And 5) Thresholds, Chien-Nan Liu, Anthony F. Starace
Photodetachment Of He- In The Vicinity Of The He* (N=3, 4, And 5) Thresholds, Chien-Nan Liu, Anthony F. Starace
Anthony F. Starace Publications
A comprehensive eigenchannel R-matrix study of photodetachment of He-(1 s2s2p 4P0 (1 ) is presented for the energy region of the Hesnl3l) thresholds, where 3<~n<~5. Over this energy region we present all partial cross sections which have been measured experimentally, including theoretical predictions (1 for the Hes3p 3P ( ) partial cross section, as well as energies and widths for all resonances, and identifications of all major ones. Near the Hen=3) thresholds, we predict two 4De resonances that to our knowledge have previously been neither predicted nor observed, and present results showing their effects on partial cross sections and photoelectron angular distributions; …
Intensity Dependence Of Plateau Structures In Laser-Assisted X-Ray–Atom Scattering Processes, Dejan B. Miloševic, Anthony F. Starace
Intensity Dependence Of Plateau Structures In Laser-Assisted X-Ray–Atom Scattering Processes, Dejan B. Miloševic, Anthony F. Starace
Anthony F. Starace Publications
The dependence on laser intensity of recently discovered plateau structures in laser-assisted x-ray–atom scattering, both with and without a static electric field present, is analyzed. Using the “three-step” model and the strong-field approximation we demonstrate a connection between laser-assisted, x-ray–atom scattering and high-order harmonic generation: For high laser-field intensities without a static field present, both processes have plateaus whose energies extend to the cutoff value 3.17Up, where Up is the ponderomotive potential energy. For x-ray–atom scattering in the presence of a static electric field we show that at high laser-field intensities two plateaus appear: One is …
High-Order Harmonic Generation In Magnetic And Parallel Magnetic And Electric Fields, Dejan B. Miloševic, Anthony F. Starace
High-Order Harmonic Generation In Magnetic And Parallel Magnetic And Electric Fields, Dejan B. Miloševic, Anthony F. Starace
Anthony F. Starace Publications
We demonstrate control of high-harmonic generation (HHG) by a linearly polarized laser field using uniform static magnetic and electric fields parallel to the laser polarization. We show that the harmonic intensity can be considerably increased for particular values of the magnetic field. The maximum values of the harmonic intensity correspond to such values of magnetic induction for which an integer multiple of the classical cyclotron period of the electron’s motion perpendicular to the magnetic field is equal to the return time of the ionized electron wave packet to the nucleus under the influence of the laser field (and static electric …
Dc Field-Induced, Phase And Polarization Control Of Interference Between One- And Two-Photon Ionization Amplitudes, N. L. Manakov, V.D. Osiannikov, Anthony F. Starace
Dc Field-Induced, Phase And Polarization Control Of Interference Between One- And Two-Photon Ionization Amplitudes, N. L. Manakov, V.D. Osiannikov, Anthony F. Starace
Anthony F. Starace Publications
We demonstrate that a weak, static electric field enables nearly complete coherent phase control of the total ionization yield in a two-color ionization process using fundamental and second-harmonic radiation. The static electric field induces a dipole-forbidden resonance in the two-photon transition amplitude so that the final photoelectron states are identical to those in a single photon transition. We demonstrate also a phase controllable circular dichroism effect in the total photoelectron yield. Experimental realization of this process using alkali metal atoms is discussed.
Photodetachment Of Na-, Chien-Nan Liu, Anthony F. Starace
Photodetachment Of Na-, Chien-Nan Liu, Anthony F. Starace
Anthony F. Starace Publications
Eigenchannel R-matrix calculation results are presented for the photodetachment partial cross sections of Na- for energies up to the Na(5p) threshold. The photoelectron angular distribution asymmetry parameter for the process Na-+γ→Na(3p)+e- is also presented over the same energy range. Detailed analyses and identifications of 1P0 resonance structures are presented and compared with corresponding ones in H- and Li-. Our results are compared with works of others, including the four-state close-coupling results of Moores and Norcross [Phys. Rev. A 10, 1646 (1974)], the resonances observed by Johnston and …
Phase Control Of X-Ray–Atom Scattering In The Presence Of A Bichromatic Laser Field, Dejan B. Miloševíc, Anthony F. Starace
Phase Control Of X-Ray–Atom Scattering In The Presence Of A Bichromatic Laser Field, Dejan B. Miloševíc, Anthony F. Starace
Anthony F. Starace Publications
We consider the scattering of 50 eV x-rays by hydrogen atoms in the presence of a bichromatic, linearly polarized laser field with frequencies ω and rω, where r = 2, 3, ω = 1.17 eV, and with relative phase &#; between the bichromatic laser field components. Numerical results for the differential cross-section (DCS) as a function of the number n, where nω is the energy exchanged with the laser field, are presented. For either a monochromatic laser field or a bichromatic laser field with the frequencies ω and 3ω, the integer n can only be even, while for a bichromatic …
Magnetic-Field-Induced Intensity Revivals In Harmonic Generation, Dejan B. Miloševic, Anthony F. Starace
Magnetic-Field-Induced Intensity Revivals In Harmonic Generation, Dejan B. Miloševic, Anthony F. Starace
Anthony F. Starace Publications
We demonstrate control of high harmonic generation by a linearly polarized laser field using a uniform static magnetic field parallel to the laser polarization. We predict that particular values of the magnetic field can increase harmonic intensities by orders of magnitude. Classical orbit calculations show that these magnetic-field-induced intensity revivals occur when the return time for laser-driven motion of the electron back to the origin is a multiple of the cyclotron period for motion perpendicular to the laser polarization direction.
Mirroring Behavior Of Partial Photodetachment And Photoionization Cross Sections In The Neighborhood Of A Resonance, Chien-Nan Liu, Anthony F. Starace
Mirroring Behavior Of Partial Photodetachment And Photoionization Cross Sections In The Neighborhood Of A Resonance, Chien-Nan Liu, Anthony F. Starace
Anthony F. Starace Publications
Partial photodetachment and photoionization cross sections corresponding to highly excited residual atoms or ions are shown analytically to mirror one another in the neighborhood of a resonance. More precisely, any two groupings of partial cross sections are shown here to have components whose variations with energy near a resonance are equal in magnitude and opposite in direction. This work extends an analysis of Starace [Phys. Rev. A 16, 231 (1977)] for the behavior of partial cross sections near a resonance to the case when the ρ2 parameter of Fano and Cooper [Phys. Rev. 137, A1364 (1965)] tends to zero.