A finite-difference model for intense light interactions with dielectrics in the ultrafast ionization regime

TL;DR

This paper introduces a computationally efficient finite-difference model for simulating the interaction of intense ultrashort laser pulses with dielectrics, capturing ultrafast plasma formation and dynamics.

Contribution

The model uniquely combines Maxwell's equations with detailed ionization and plasma dynamics, enabling accurate simulations of laser-dielectric interactions in the strong ionization regime.

Findings

Identified optimal regimes for plasma formation under various parameters.

Explained maxima in plasma generation through spatiotemporal dynamics.

Demonstrated the model's ability to simulate nanoscale plasma formation.

Abstract

We present a computationally efficient model that describes the interaction of intense, ultrashort infrared laser pulses with transparent materials in the strong ionization regime. The model is augmented with a detailed self-consistent description of the local response due to ionization and collisional plasma dynamics. It incorporates the direct solution of Maxwell's equations without approximations and rigorous boundary conditions for the input pulse, allowing us to study the ultrafast formation of over-critical nanoscaled plasmas in dielectric materials under the influence of intense tightly focused laser pulses. We perform a scan of the parameter space, find unexpected optima regimes for different experientially relevant parameters, and explain these maxima based on spatiotemporal dynamics.