Abstract

When fast electrons pass through a periodic medium, resonant transition radiation is emitted.¹ The angle of emission θ between the electromagnetic wave and the beam is related to the wavelength λ of radiation by $\sqrt{\overline{\epsilon }}\cos \theta =c/v-n\lambda /l$, where ε is the average dielectric constant, ν is the velocity of the electron, n is an integer, and l is the spatial period of interfaces.

© 1986 Optical Society of America