Abstract

Nonlinear propagation in air has been an area of active research since the first observation of laser filamentation using ultrashort laser pulses.¹ Theoretical and experimental studies have shown that the general behavior of an ultrashort pulse in air during nonlinear propagation is the compression of both the spatial and temporal profiles of the pulse during the initial phase of the nonlinear propagation. As the pulse propagates further, pulse splitting, accompanied by spectral broadening and further spatial compression occurs. Many numerical models^2-5 have been published that include effects such as the Raman effect, optical shock, ionization, electron refraction and third order dispersion to capture more complicated phenomenology such as the spectral distribution of the pulse. While these models provide insight in understanding the behavior of the nonlinear propagation of ultrashort pulses, quantitative comparisons with experimental data are still incomplete. In this paper we will present a direct comparison of experimental data with numerical simulations.

© 2002 Optical Society of America