Numerical Simulation of a Hollow-Core Woodpile-Based Mode Launcher for Dielectric Laser Accelerators

Resumen

Hollow core microstructures powered by infrared lasers represent a new and promising area of accelerator research, where advanced concepts of electromagnetism must be used to satisfy multiple requirements. Here, we present the design of a dielectric electromagnetic band gap (EBG) mode launcher?converter for high-power coupling in dielectric laser accelerators (DLAs). The device is based on a silicon woodpile structure, and it is composed of two perpendicularly coupled hollow-core waveguides?a transverse electric (TE)-like mode waveguide (excited from laser power) and a transverse magnetic (TM)-like mode (accelerating) waveguide?in analogy with the TE10" role="presentation">1010 10 -to-TM01" role="presentation">0101 01 waveguide mode converters of radio frequency (RF) linear accelerators (LINACs). The structure is numerically designed and optimized, showing insertion losses (IL) &lt;0.5" role="presentation"><0.5<0.5 < 0.5 dB and efficient mode conversion in the operating bandwidth. The operating wavelength is 5 &#x3BC;" role="presentation">µµ µ m, corresponding to a frequency of ?60 THz, in a spectral region where solid-state continuous-wave (CW) lasers exist and are actively developed. The presented woodpile coupler shows an interaction impedance in the order of 10 k&#x3A9;" role="presentation">OO O , high power handling and efficiency.