Strong Ionization in carbon Nanowires

TL;DR

This study uses 3D PIC simulations to analyze ionization dynamics in carbon nanowire arrays under intense laser irradiation, revealing full ionization after 30 cycles and a slightly stronger effect with circular polarization.

Contribution

First detailed simulation analysis of ionization in carbon nanowires under different laser polarizations at this scale.

Findings

Nanowires fully ionized after about 30 laser cycles

Circular polarization induces slightly stronger ionization

Nanowire arrays enhance laser energy absorption and electron acceleration

Abstract

Surfaces covered with nanostructures, such as nanowire arrays, have shown to facilitate a significantly higher absorption of laser energy as compared to flat surfaces. Due to the efficient coupling of the laser energy, highly energetic electrons are produced, which in turn can emit intense ultrafast X-ray pulses. In the present work we use full three dimensional PIC simulations to analyze the behavior of arrays of carbon nanowires $400 nm$ in diameter, irradiated by a $\lambda_0 = 400 nm$ laser pulse of $60 fs$ duration at FWHM and a vector potential of $a_0 = 18$. We analyze the ionization dynamics of the nanowires. We investigate the difference of the ionization strength and structure between linearly and circularly polarized laser beam. The nanowires are found to be fully ionized after about 30 laser cycles. Circularly polarized light reveals a slightly stronger ionization effect.