(Submitted on 18 Jan 2013)
Ultrarelativistic charged particles are predicted to emit hard electromagnetic radiation of undulator type while channeling in a crystal with periodically bent crystallographic planes. The recently proposed crystalline undulator with a bending amplitude smaller than the distance between the bent planes and a bending period shorter than the period of channeling oscillations is far superior to what was proposed previously. In the same time, it is more challenging from the technical point of view because its bending period has to be in the sub-micron range. It is shown that a mixed crystal of silicon-germanium with properly varying germanium fraction can have the necessary bending parameters. Moreover, it is predicted to be stable against misfit dislocations.
Comments: 6 pages, 2 figures
По крайней мере, есть хорошая картинка, показывающая, как наличие гетероструктуры в кристалле приводит к изгибу плоскостей.