Optimum conditions for electron acceleration using tightly focused laser beams

Abstract

We investigate optimum conditions for achieving maximum energy gain when electrons are scattered by tightly focused laser beams. A single-beam configuration and one that employs two beams crossing at an angle are discussed. Solution of the equations of motion is carried out numerically in each case, and the fields are modeled by those of a Gaussian beam to order 5, where is the beam diffraction angle. It is shown that the gain in the GeV range may be obtained when MeV electrons are scattered by petawatt laser beams of a few micron waist radii.