Investigations are currently being made to miniaturize particle accelerators. One of the main approaches to achieve this is by the use of a laser for particle acceleration instead of the conventional method with radio frequency waves. One of the first experiments towards this direction was reported in . The experiment uses a silica grating structure  for guiding of particles. An 800 nm mode-locked Ti:sapphire laser is shone across the guiding channel. The acceleration channel consists of surfaces with ridges in order to shape the electric field pattern in a way to enhance energy transfer to electrons.
This article presents a basic study of this approach via simulation. The laser pulse is realized with a plane wave excitation just above the silica structure. The pattern of the resulting electric field component along the beam path is shown in Figure 2. The field has a normal incidence with respect to the beam path. The grating structure provides a periodic modulation of the electric field inside the vacuum channel, according to the principle of periodic field reversal . This results in an overall gain in the energy of particles as they pass through the channel under the influence of this field....
A 60 MeV electron beam is shot into the guiding channel of the structure. The field simulation of the structure is carried out using the Transient solver in CST STUDIO SUITE®. It is then combined with the PIC solver for a self-consistent simulation to study the interaction between fields and particles. The particles get bunched as they pass through the channel, as can be seen in Figure 3.
 E. A. Peralta et al., "Demonstration of Electron Acceleration in a Laser-Driven Dielectric Microstructure", Nature (London) (2013)
 T. Plettner, P. P. Lu, R. L. Byer, "Proposed few-optical cycle laser-driven particle accelerator structure" Phys. Rev. ST Accel. Beams 9, 111301 (2006)
 E. A. Peralta, "Acceleration of electrons in a laser driven dielectric microstructure", NA-PAC'13, Pasadena, CA, (September 30, 2013)
 J. England, "Making Accelerators on Microchips", Keynote Address?, SLAC Years of Service Awards (March 19, 2015)