Coulomb-corrected quantum interference in above-threshold ionization: Working towards multitrajectory electron holography

Abstract

Using the recently developed Coulomb Quantum Orbit Strong-Field Approximation (CQSFA), we perform a systematic analysis of several features encountered in above-threshold ionization (ATI) photoelectron angle-resolved distributions (PADs), such as side lobes, and intra-and intercycle interference patterns. The latter include not only the well-known intra-cycle rings and the near-threshold fan-shaped structure, but also previously overlooked patterns. We provide a direct account of how the Coulomb potential distorts different types of interfering trajectories and changes the corresponding phase differences, and show that these patterns may be viewed as generalized holographic structures formed by up to three types of trajectories. We also derive analytical interference conditions and estimates valid in the presence or absence of the residual potential, and assess the range of validity of Coulomb-corrected interference conditions provided in the literature.

Holographic detection of parity in atomic and molecular orbitals

“…The laser peak intensity is chosen as 6.5 × 10 13 W/cm 2 here. The interferences between types I and II (II and III) trajectories are responsible for the fan-shaped (spiderlike) structures [11,27,28]. The carpetlike structures result from the interferences between type-III and type-IV trajectories along the transverse direction [12].…”

“…For instance, one may use sculpted fields [8], where Coulomb effects have been approximated by a simple eikonal phase, or interference carpets, whose explanation ignores the residual Coulomb potential [9]. However, Coulomb distortion represents a troublesome issue for directly probing parity, as it modifies the interfering trajectories themselves [10][11][12]. This includes the number of trajectories, their shapes, initial momenta, and ionization times.…”

Effects of the Coulomb potential in interference patterns of strong-field holography with photoelectrons

“…We begin our analysis of effects of the Coulomb potential with the intracycle interference, i.e., the interference of reference (direct) electrons starting from two different quarters of the laser period, see, e.g., Refs. [43,49,63,64]. The corresponding interference patterns produced by the reference electrons launched on the first and on the second quarter of the period calculated within the three-step model and with the account for the Coulomb field are shown in Figs.…”

“…[38][39][40][41][42]) and theoretically [35, 37-39, 41, 43-49]. Among the theoretical approaches used to analyze the holographic structures are: the semiclassical model that accounts for the laser field only [41,[43][44][45][46], direct numerical solution of the TDSE [35,38,39,41,43], the modified version of the SFA that accounts for the rescattering [35,37], the Coulomb-corrected strong-field approximation (CCSFA) [35,37], and the Coulomb quantum orbit strong-field approximation (CQSFA) [48,49] (see Ref. [50] for the foundations of the CQSFA method).…”

“…The distortion of different kinds of interfering trajectories along with the change of the phase difference between them due to the presence of the ionic potential was studied in Ref. [49]. However, no direct comparison of the interference structures predicted by the three-step model with those calculated taking the Coulomb potential into account has been made so far.…”