Input Coupling for Photonic Bandgap Fiber Accelerators

Dielectric hollow-core optical fibers have been proposed as a means of confining a traveling wave mode in order to produce a micron-scale laser-driven particle accelerator. A calculation of the power coupling to the confined accelerator mode for this type of structure is complicated by the presence of unconfined or leaky modes. We propose a computational method for resolving this issue, and evaluate the coupling efficiency of laser light into several proposed structure geometries using the frequency-domain code HFSS.