Abstract

The development of intense (⪆ 10¹⁵ W/cm²) ultrashort-pulse (⪅ 1 ps) laser systems has opened up possibilities for experiments on plasma creation in which multiphoton or tunneling ionization plays a dominant role. This paper presents a one-dimensional model which couples Maxwell’s equations and multiphoton ionization rates in order to simulate the propagation of a femtosecond laser pulse through an initially-neutral atmospheric-density rare gas. There are two distinct aspects to this problem: the plasma-induced self-phase modulation of the laser pulse, which leads to a blue shift and spectral broadening; and the properties of the plasma, in particular, the relatively low temperature and high degree of ionization.

© 1992 IQEC