Effects of electric field polarizations on pair production

TL;DR

This study numerically investigates how electric field polarization affects vacuum pair production, revealing polarization-dependent interference patterns and particle number densities, with implications for understanding strong-field quantum phenomena.

Contribution

It provides new insights into the influence of electric field polarization on pair production using the real-time Dirac-Heisenberg-Wigner formalism, especially in multi-cycle and few-cycle fields.

Findings

Interference patterns in momentum spectra depend on field cycle number.

Particle number density varies nonlinearly with polarization and laser frequency.

Momentum distribution splits and forms rings as polarization increases.

Abstract

The effects of electric field polarizations on pair production from a vacuum are investigated numerically by employing the real-time Dirac-Heisenberg-Wigner formalism. For few-cycle fields, it is found that the interference pattern in momentum spectra is absent and the circular distortion of momentum distribution becomes more apparent with the increase of polarization. For multi-cycle fields, it is found that the interference effects in momentum spectra are obvious. And as the polarization increases, the momentum distribution is split into two parts in the momentum $q_y$ direction first and then two separated parts are connected into a ring. The effects of polarizations on the number density of created particles exhibits two different characteristics. For a small laser frequency, the particle number density deceases with the polarization, while for a large laser frequency, the relation between them is sensitive to the field frequency nonlinearly. Some interpretations for the obtained results in this study, which is expected to be valuable to deepen the understanding of pair production in complex fields and also helpful for the study associated to strong-field ionization.