摘要

We study the nonparaxial and vectorial effects of ultrashort, intense, pulsed laser beams propagating in gaseous media by using an order-of-magnitude analysis. A near vector wave equation is derived, which includes the effects of the coupling between the transverse and the longitudinal components of the laser field and is valid for an arbitrarily short laser pulse. In addition; we obtain the equation governing the time evolution of the plasma current density, which can be used to analyze the mechanism of energy loss during propagation of the laser pulse.