Dielectric materials (quartz, diamond, garnets,. . .) employed for
dielectric-wakefield acceleration (DWAC) would have higher
breakdown limits than metal. The dielectric structures, e.g. with
an aperture of several 100 nm at k = 800 nm [45], would be driven
in the THz range, at optical wavelengths or in the near-IR regime,
and provide accelerating gradients of 1–3 GV/m. They could be
excited by an e- beam or by a laser (either by an external fiber laser
or by an integrated semiconductor laser) [17].