Scattering of electrons by intense coherent light

Abstract
We report the first direct observation of electron inelastic scattering from the pondermotive potential of an intense laser pulse in vacuum. Electrons gained up to 0.2 eV when scattered from the temporal leading edge of a 1064-nm (1.165 eV), 140-psec laser pulse, and lost comparable amounts of energy when scattered from the trailing edge. When directed to the most intense part of the pulse, they were deflected out of the beam.