Possibility of Prolific Pair Production with High-Power Lasers

Prolific electron-positron pair production is possible at laser intensities approaching ${10}^{24}\text{ }\text{ }\mathrm{W}\text{ }{\mathrm{cm}}^{\ensuremath{-}2}$ at a wavelength of $1\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$. An analysis of electron trajectories and interactions at the nodes ($B=0$) of two counterpropagating, circularly polarized laser beams shows that a cascade of $\ensuremath{\gamma}$ rays and pairs develops. The geometry is generalized qualitatively to linear polarization and laser beams incident on a solid target.