LAUSR

Accelerator Physics Electron or particle accelerators are usually imagined only as large national or multinational facilities. However, efforts are under way to shrink the size of particle accelerators to table-top- or even chip-scale using powerful laser pulses. Confining and focusing an electron beam on the micrometer scale of a chip is a challenge. Black et al. developed a laser driven, tunable electron lens using a patterned microstructured array of silicon pillars. Laser illumination of the dielectric structures generate huge fields that confine and focus the electron beams between the pillars, effectively creating an electron lens with a focal length on the scale of around 50 micrometers. The ability to tune the energy of the electrons and focal length of the lens should prove useful in the further development of miniaturized electron accelerators. Phys. Rev. Lett. 122 , 104801 (2019).