Favorable target positions for intense laser acceleration of electrons in hydrogen-like, highly-charged ions

Abstract

Classical relativistic Monte Carlo simulations of petawatt laser acceleration of electrons bound initially in hydrogen-like, highly-charged ions show that both the angles and energies of the laseraccelerated electrons depend on the initial ion positions with respect to the laser focus. Electrons bound in ions located after the laser focus generally acquire higher (%GeV) energies and are ejected at smaller angles with respect to the laser beam. Our simulations assume a tightly-focused linearly-polarized laser pulse with intensity approaching 10 22 W/cm 2 . Up to fifth order corrections to the paraxial approximation of the laser field in the focal region are taken into account. In addition to the laser intensity, the Rayleigh length in the focal region is shown to play a significant role in maximizing the final energy of the accelerated electrons. Results are presented for both Ne

Superponderomotive regime of tunneling ionization

“…Existing literature dealing with finite spot size effects in tunneling ionization includes Refs. [3,4,[15][16][17][18], among others. The analysis, calculations, and experiments considered in Refs.…”

“…Refs. [15,16] discuss phase resonance, but lack analytical treatment, and discussion of scaling with irradiance. Refs.…”

“…Refs. [15,16] utilize a classical model for the bound states, whereas the two-step model used here employs a quantum mechanical ionization rate [9], and includes radiation reaction during the classical motion. This approach produces highly resolved S-matrix and momentum distributions which are, in principle, observable quantities that can be correlated with sub-cycle bursts of ionization current, and may be useful for particle acceleration applications.…”

Discontinuities in the electromagnetic fields of vortex beams in the complex source-sink model

“…Experimentally, the highest laser intensities are obtained using tight focusing techniques, in which the laser spot size in the focal region is comparable to the laser field wavelength. Theoretical simulations of laser-matter interactions under such tight focusing conditions require a detailed description of the laser fields in the focal region that goes beyond the paraxial approximation [3][4][5][6][7][8][9].…”