Nonsinusoidal few-cycle pulsed light beams in free space

Abstract

We study a family of nonseparable solutions of the three-plus-one-dimensional paraxial wave equation in free space that represent ultrashort waveforms localized in time and space. We use them to develop a simple model for the spatiotemporal structure of ultrashort pulsed light beams, with only one or a few field oscillations of a nonsinusoidal nature. In the many-oscillation limit the model approaches the widely used separable models of modulated sinusoidal oscillations in time and of a Gaussian beam in space.