Low-Intensity Laser-Electron Scattering In The Thomson Limit

Within the context of laser-electron scattering for low intensities of the incoming photon beam, we present a discussion of the leading multiphoton reaction, two-photon absorption by a free electron in a Compton-like process. The two-photon angular distribution is calculated in quantum electrodynamics and compared with existing classical and semiclassical calculations in the Thomson limit. We find that for incident linearly polarized beams all such calculations agree in this limit. Furthermore, the present approach allows us to study the possible effect of the quantum-mechanical correlation of pairs of coincident photons, i.e., the degree of second-order coherence