Superfilamentation in air

TL;DR

This paper introduces superfilamentation, a new laser propagation regime in air where multiple filaments merge into fewer, denser filaments with higher intensity and plasma density, supported by experimental and numerical evidence.

Contribution

It reports the discovery of superfilamentation, a novel regime characterized by denser plasma and fewer filaments, validated through experiments and simulations.

Findings

Plasma density is ten times higher than in standard filaments.

Superfilamentation involves fewer filaments with higher intensity.

Numerical simulations agree well with experimental results.

Abstract

The interaction between a large number of laser filaments brought together using weak external focusing leads to the emergence of few filamentary structures reminiscent of standard filaments, but carrying a higher intensity. The resulting plasma is measured to be one order of magnitude denser than for short-scale filaments. This new propagation regime is dubbed superfilamentation. Numerical simulations of a nonlinear envelope equation provide good agreement with experiments.