Date of this Version
Reviews of Modern Physics (July-September 2007) 79(3): 929-941. DOI: 10.1103/RevModPhys.79.929. PACS number(s): 03.75.-b, 42.50.Vk, 61.14.-x.
The observation of the Kapitza-Dirac effect raises conceptual, theoretical, and experimental questions. The Kapitza-Dirac effect is often described as diffraction of free electrons from a standing wave of light or stimulated Compton scattering. However, for the two-color Kapitza-Dirac effect these two interpretations appear to lead to paradoxical conclusions. The discussion of this paradox deepens our understanding of both of these versions of the Kapitza-Dirac effect.