Model for ultrashort laser pulse-induced ionization dynamics in transparent solids

Jeremy R Gulley,Thomas E Lanier

doi:10.1103/physrevb.90.155119

Abstract

A comprehensive model of ultrafast laser-induced plasma generation intended for coupling with pulse propagation simulations in transparent solids is introduced. It simultaneously accounts for the changing spectrum of a propagating ultrashort laser pulse while coupling to the evolution of the energy-resolved nonequilibrium free-carrier distribution. The presented results indicate that strong pulse chirps lead to ionization dynamics that are not captured by the standard monochromatic treatment of laser-induced plasma formation. These results have strong implications for ultrafast laser-solid applications that depend on ionization in a strong nonlinear focus.

Highlights

Ultrafast nonlinear pulse propagation and laser-induced ionization in bulk media are interrelated research areas with broad and promising applications
To achieve greater fidelity to the fundamental physics of carrier scattering dynamics, pulse propagation simulations could model laser-plasma interactions in dielectric solids with models based on the quantum kinetic approaches often used to study semiconductors. This paper introduces such a model based on a set of free-carrier energy-resolved descriptions referred to as extended multirate equations
A comprehensive model of ultrafast laserinduced plasma dynamics intended for coupling with pulse propagation simulations in transparent solids was introduced

Summary

Introduction

Ultrafast nonlinear pulse propagation and laser-induced ionization in bulk media are interrelated research areas with broad and promising applications. To elucidate the physics of these applications, one must simultaneously model the propagation of the laser field and its interaction with the material [5] These combined areas of research present a challenge for theoretical calculations due in large part to the computing requirements of combining fully three-dimensional (3D) pulse propagation simulations with detailed calculations of laserplasma dynamics. Each of those calculations is cumbersome individually, and combining them typically involves using a detailed model of one process and a simplified model of the other. Such approaches contain many inconsistencies and oversimplifications [6]

Results

Discussion

Conclusion