Disk-loaded RF waveguide matching techniques applied to silicon woodpile accelerator
- Stanford Linear Accelerator National Laboratory 2575 Sand Hill Road, Menlo Park, CA 95051 (United States)
Silicon woodpile photonic crystal provides a three-dimensional dielectric waveguide system for high-gradient laser driven acceleration. The woodpile waveguide is periodically loaded in the longitudinal direction; therefore simple cross-sectional mode profile matching is not sufficient to launch the accelerating mode appropriately and will result in significant scattering loss. Hinted by the common nature of longitudinal periodicity between disk-loaded waveguide and woodpile waveguide, several coupler design schemes developed for multi-cell RF cavity are implemented in the woodpile accelerator design. Among them there are the travelling-wave match method based on S-matrix, the periodic VSWR method, and the TE-to-TM coupling iris design. This paper presents design procedures and simulation results using these methods. According to simulations, nearly 100% power transmission between SOI and woodpile waveguides with a travelling-wave match is achieved with a specially designed mode-launching coupler. Constructed by silicon rods extruding into the defect waveguide, the coupling iris provides necessary transition from TE mode to TM accelerating mode, also with negligible coupling loss.
- OSTI ID:
- 22075883
- Journal Information:
- AIP Conference Proceedings, Vol. 1507, Issue 1; Conference: 15. advanced accelerator concepts workshop, Austin, TX (United States), 10-15 Jun 2012; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Low-Field Accelerator Structure Couplers and Design Techniques
Design of On-chip Power Transport and Coupling Components for a Silicon Woodpile Accelerator