Bragg scattering of free electrons using the Kapitza-Dirac effect.

Bragg scattering has been observed for free electrons using a standing wave of light. Both the rocking curve and the angular electron distribution have been measured. The results of a numerical simulation to the Schrödinger equation are consistent with our experimental data. Unlike the diffraction regime which uses thin crystals, the Bragg regime requires the use of thick crystals. We point out several applications in atom optics that could be realized in electron optics.