Optimized silicon asymmetric dual-pillar grating for dielectric laser acceleration of subrelativistic electrons with enhanced accelerating gradient

Dielectric laser accelerator has great potential for the miniaturization of particle accelerators. We present results of the numerical investigation of a silicon dual-pillar grating structure with a high accelerating gradient for subrelativistic electrons. An asymmetric configuration is utilized to generate an accelerating mode with lower skew. Driven by a 1550 nm laser with a peak fluence of 20 mJ/cm² and a pulse length of 100 fs, the structure could achieve a maximum gradient of 0.42 GV/m for 50 keV electrons. (author)