Dual-grating dielectric accelerators driven by a pulse-front-tilted laser

Abstract

This paper investigates numerically dual-grating dielectric laser-driven accelerators driven by a pulse-front-tilted (PFT) laser, which extends the interaction length and boosts the electrons' energy gain. The optical system necessary to generate PFT laser beams with an ultrashort pulse duration of 100 fs is also studied in detail. Through two-dimensional particle-in-cell simulations, we show that such a PFT laser effectively increases the energy gain by (91±25) % compared to that of a normally incident laser with a waist radius of 50 μm for a 100-period dual-grating structure.

Energy efficiency studies for dual-grating dielectric laser-driven accelerators

“…As described in Ref. [17], we achieve − = 0 when electrons move at a speed = which matches with tilt angle . In this case, the energy gain is…”

“…As calculated in Ref. [17], an interaction length of int ′ = 51 μm is obtained for an incident laser waist radius z = 50 µm. When such a front-tilted pulse propagates through the structure to interact with the electron bunch within it, the maximum energy gain is calculated to be ∆ PFT ≈ p √ int ′ = 90 keV using Eq.…”

“…The calculated interaction length is int = ( The same laser parameters are used for the optical system described in Ref. [17], to generate a front-tilted pulse with an ultrashort pulse duration 0 = 100 fs and a tilt angle = 45 0 . As calculated in Ref.…”

“…This scheme would effectively increase the energy efficiency by more than 100 % compared to that of normally-incident laser illumination, as studied in Ref. [17].…”

Optical design for increased interaction length in a high gradient dielectric laser accelerator

“…We have described the design and characterization of a free space optical system for studying extended interactions in DLA. This experimental technique should prove valuable for a number of proposed experiments [23,24] intending to use a tilted pulse front. By application to DLA tests at the Pegasus facility we show how pulse distortions may be controlled in order to optimize acceleration and allow for beam dynamics to dominate the interaction.…”