Rescattering nonsequential ionization of Ne3+, Ne4+, Ne

Abstract

The ionization of Ne and Kr at 400 nm has been measured from 10 13 to 10 17 W/cm 2 for charge states up to Kr 8+ . Nonsequential ionization is seen in the higher charge states Ne 3+ , Ne 4+ , Ne 5+ , Kr 5+ , Kr 6+ , Kr 7+ , and Kr 8+ when the atomic response to the increasing external field strength moves from multiphoton to tunneling. A similar development in nonsequential ionization is seen in a semiclassical model and an empirical model of rescattering. The models show that nonsequential ionization not apparent in lower charge states can become prominent for higher charge states. It is possible to generalize these results and predict optimal wavelengths for multielectron excitation via nonsequential ionization. The findings indicate that ultraviolet to vacuum ultraviolet wavelengths can give the largest recollision for higher charge states.

Quantitative rescattering theory for nonsequential double ionization*

“…In (a), the present simulations are compared with the experimental data of Sheehy et al, [82] the TDSE calculations of Parker et al, [12] and the calculations of van der Hart and Burnett [40] based on the rescattering model. All experimental data points were shifted to higher intensity by 50%, as suggested by Parker et al [12] In (b), the present results are compared with the experimental data of Ekanayake et al [83] Adapted from Ref. [36].…”

“…Using the improved QRS model, Chen et al [35,36,38] have recently calculated the double-to-single ionization ratios for He and Ne in intense fields with various different laser parameters, and the numerical results were found to be in good accordance with the experimentally measured data. [5,[82][83][84][85] Figure 7 shows the double-to-single ionization ratios simulated by the QRS model for He in a 120 fs pulse with a wavelength of 390 nm and for Ne in a 40 fs pulse with a wavelength of 400 nm, respectively. In both cases, the results of the QRS model are in remarkably good agreement with the experimental measurements [82,83] over the whole range of laser intensity.…”

“…[5,[82][83][84][85] Figure 7 shows the double-to-single ionization ratios simulated by the QRS model for He in a 120 fs pulse with a wavelength of 390 nm and for Ne in a 40 fs pulse with a wavelength of 400 nm, respectively. In both cases, the results of the QRS model are in remarkably good agreement with the experimental measurements [82,83] over the whole range of laser intensity. It should be noted that, in Fig.…”

“…7(a) the measured intensities are multiplied by 1.5, as suggested by Parker et al [12] who performed the corresponding TDSE calculations, and in Fig. 7(b) the experimental data of the double-to-single ionization ratio for Ne were deduced from the total ionization yields of Ne 2+ and Ne + measured by Ekanayake et al [83] One can see from Fig. 7(a) that the QRS model also reproduces the TDSE results of Parker et al [12] very well, except for the intensities below 5.0 × 10 14 W/cm 2 .…”

A general model and toolkit for the ionization of three or more electrons in strongly driven atoms using an effective Coulomb potential for the interaction between bound electrons

“…These studies include classical models with reduced-dimensionality [8] and with soft core Coulomb potentials [9][10][11][12][13], reduceddimensionality quantum mechanical treatments [14][15][16] and semi-classical models with Heisenberg potentials [17]. On the experimental front, several studies have addressed multi-electron ionization in strongly-driven Ar and Ne [18][19][20][21][22][23][24]. For weak fields, striking angular patterns of three-electron escape and the underlying collision mechanisms were identified with 3D semi-classical models and ab-initio quantum mechanical techniques [25][26][27][28].…”