Charged-Particle Scattering in the Presence of a Strong Electromagnetic Wave

Electron-ion interaction effects in attosecond time-resolved photoelectron spectra

“…In this work, we focus on the effect of simultaneous ir-laser pulse and Coulomb interactions on streaked photoemission spectra from the prototypical ground state of a one-dimensional (1D) hydrogen atom. This Coulomb-laser (CL) coupling effect was first investigated by Kroll and Watson [10] in their study of laser-assisted atomic scattering. It also affects the spectra of high harmonic generation, multiphoton ionization, and laser-assisted xuv photoionization.…”

Cutoffs of high-energy plateaux for atomic processes in an intense elliptically polarized laser field

“…As shown in [3], this result is equivalent to the Kroll-Watson (low-frequency) approximation [19] and describes the low-energy part (the 'K-plateau') of the electron spectrum. Using (17), the integral over t in the amplitude (2) may be estimated by the saddle point method, where the saddle points, t = t i (i = 1, 2, ...), are given by (18) Analysis shows that the amplitude (2) oscillates as a function of n for real values of t i and has an exponential smallness for complex t i .…”

“…Thus the position of the K-plateau cutoff corresponds to the minimum value of p n at which the roots t i of equation (18) acquire an imaginary part. The extent of the K-plateau reaches a maximum when the vectors p and p n are collinear with the major axis of the polarization ellipse: (19) where the signs ∓ correspond to parallel/antiparallel directions of p and p n . Thus, for the case of backscattering, the low-energy K-plateau exists for any p, while for forward scattering it exists only for incoming electron energies E = p 2 less than (1 + )u p and its maximum extent, E n,max = 4(1 + )u p , is reached at E → 0.…”

“…(b) Energy distribution of scattered electrons (for forward scattering along the major axis of the polarization ellipse) for F = 0.5, ω = 0.155, E = 3.1775 = 20.5ω = 0.61u p , and for different values of (indicated in fi gure). Hollow and fi lled vertical arrows show the K-and R-plateau cutoffs given respectively by (19) and (21), (22). The vertical line corresponds to the case of elastic scattering, p 2 n = E.…”

“…In fi gure 2(b) we present the energy distribution of electrons for forward scattering along the major polarization axis (calculated using the exact results [3] for the scattering amplitude A n ), where the vertical arrows indicate the cutoff positions given by equations (19), (21) and (22). (For e -H scattering, these results correspond to an incoming electron energy of 2.4 eV and a CO 2 laser fi eld (λ = 10.6 μm) of intensity 3.7 × 10 11 W cm -2 .)…”