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Full-Text Articles in Physics
Perturbative Calculation Of The Triply Differential Cross Section For Photo-Double-Ionization Of He, Andrei Y. Istomin, N. L. Manakov, Anthony F. Starace
Perturbative Calculation Of The Triply Differential Cross Section For Photo-Double-Ionization Of He, Andrei Y. Istomin, N. L. Manakov, Anthony F. Starace
Anthony F. Starace Publications
Single-photon, two-electron ionization of He is analyzed, taking into account electron correlation using lowest-order perturbation theory and including all individual electron angular momenta in the final two-electron continuum. Perturbative account of electron correlation in the final state, which describes the so-called TS-1 mechanism of double photoionization, combined with a variational account of electron screening, is found to provide results for the triply differential cross section at an excess energy of 20 eV that are in excellent agreement with both absolute experimental data and results of non-perturbative calculations, for all kinematics of the process in which the TS-1 mechanism is expected …
Two-Photon Bremsstrahlung Processes In Atoms: Polarization Effects And Analytic Results For The Coulomb Potential, A. A. Krylovetskiĭ, N. L. Manakov, S. I. Marmo, Anthony F. Starace
Two-Photon Bremsstrahlung Processes In Atoms: Polarization Effects And Analytic Results For The Coulomb Potential, A. A. Krylovetskiĭ, N. L. Manakov, S. I. Marmo, Anthony F. Starace
Anthony F. Starace Publications
The partial wave analysis of two-photon free–free (bremsstrahlung) electron transition cross sections during scattering by a static potential U(r), as well as by an atom with a nonzero angular momentum, is carried out. The dipole interaction with radiation is taken into account in the second order of perturbation theory for the general case of elliptic polarization of photons. The polarization and angular dependences of the twophoton potential scattering amplitude is presented as a combination of the scalar product of electron momenta and photon polarization vectors and five atomic parameters containing Legendre polynomials of the scattering angle as …
Plateau Effects In The Spectra Of Electrons Scattered From Atoms In A Strong Laser Field, N. L. Manakov, Anthony F. Starace, A. V. Flegel, M. V. Frolov
Plateau Effects In The Spectra Of Electrons Scattered From Atoms In A Strong Laser Field, N. L. Manakov, Anthony F. Starace, A. V. Flegel, M. V. Frolov
Anthony F. Starace Publications
An exact quantum solution of the problem of electron scattering from a short-range potential in the presence of a strong elliptically polarized laser field is obtained. The differential scattering cross section as a function of the number of absorbed (or emitted) photons exhibits a plateau caused by the rescattering of electrons from the scattering center. Numerical results for a linearly polarized laser field are presented, and it is shown that the plateau boundaries agree well with classical estimates.
Gev Electrons From Ultraintense Laser Interaction With Highly Charged Ions, S.X. Hu, Anthony F. Starace
Gev Electrons From Ultraintense Laser Interaction With Highly Charged Ions, S.X. Hu, Anthony F. Starace
Anthony F. Starace Publications
Ultraintense laser interactions with highly charged ions are investigated using three-dimensional Monte Carlo simulations. Results show that ultraenergetic GeV electrons may be produced for highly charged ions chosen so that their electrons remain bound during the rise time of the laser pulse, and so that the electrons are ionized when the laser is near its maximum amplitude, which satisfies the best injection condition for subsequent laser acceleration.
Threshold-Related Enhancement Of The High-Energy Plateau In Above-Threshold Detachment, Bogdan Borca, M.V. Frolov, N.L. Manakov, Anthony F. Starace
Threshold-Related Enhancement Of The High-Energy Plateau In Above-Threshold Detachment, Bogdan Borca, M.V. Frolov, N.L. Manakov, Anthony F. Starace
Anthony F. Starace Publications
We present nonperturbative theoretical results showing a resonant-like enhancement of above-threshold detachment spectra in the region of the high-energy plateau as the laser intensity sweeps across channel thresholds. This enhancement has a pure quantum origin stemming from well-known threshold phenomena in multichannel problems whose features are clearly demonstrated in our numerical results. Similar well-known anomalies at neutral atom thresholds are expected to explain experimentally observed resonant-like enhancements of above-threshold ionization spectra.
Anisotropy And Magnetic Field Effects On The Entanglement Of A Two Qubit Heisenberg Xy Chain , G. Lagmago Kamta, Anthony F. Starace
Anisotropy And Magnetic Field Effects On The Entanglement Of A Two Qubit Heisenberg Xy Chain , G. Lagmago Kamta, Anthony F. Starace
Anthony F. Starace Publications
We investigate the entanglement of a two-qubit anisotropic Heisenberg XY chain in thermal equilibrium at temperature T in the presence of an external magnetic field B along the z axis. By means of the combined influences of anisotropic interactions and a magnetic field B, one is able to produce entanglement for any finite T, by adjusting the magnetic field strength. This contrasts with the isotropic interaction or the B = 0 cases, for which there is no entanglement above a critical temperature Tc that is independent of the external B field.
Nontunneling High-Order Harmonics From Ultra-Intense Laser-Driven Tightly Bound Systems, S. X. Hu, Anthony F. Starace, W. Becker, W. Sandner, D. B. Milosevic
Nontunneling High-Order Harmonics From Ultra-Intense Laser-Driven Tightly Bound Systems, S. X. Hu, Anthony F. Starace, W. Becker, W. Sandner, D. B. Milosevic
Anthony F. Starace Publications
High-order harmonic emission is investigated by numerical solution of the weakly relativistic, two-dimensional Schrödinger equation for the case of ultra-intense laser-driven tightly bound systems (for example, multiply charged ions such as O7+ exposed to laser fields of the order of 1018 W cm-2 at 248 nm). In contrast to their usual substantial decrease, the low-order harmonics having an energy less than the ionization potential exhibit a high efficiency (i.e. intense) plateau with a well defined cutoff. The shape of this plateau is found to depend on the shape of the binding potential. A classical “surfing” mechanism for …
Multipole Expansions Of Irreducible Tensor Sets And Some Applications, N. L. Manakov, A. V. Meremianin, Anthony F. Starace
Multipole Expansions Of Irreducible Tensor Sets And Some Applications, N. L. Manakov, A. V. Meremianin, Anthony F. Starace
Anthony F. Starace Publications
A formal multipole expansion of tensor functions dependent on several vector parameters is obtained in an invariant differential form. We apply this result to derive multipole expansions of finite rotation matrices in terms of finite sums of bipolar harmonics. The multipole expansion in terms of bipolar harmonics of unit vectors r1 and r2 are analyzed for functions of the type f (r)Ylm( r) (with r = r1 − r2), which are important in two-center problems. As another example of the application of the multipole expansion technique, reduction formulae are obtained for tensor constructions …