• F. Gao, W. Gai, W. Liu
  ANL, Argonne
• F. Gao, T. Wong
  Illinois Institute of Technology, Chicago, Illinois
• C.-J. Jing
  Euclid TechLabs, LLC, Solon, Ohio

We report on the design of a dual-frequency higher-order-mode dielectric-loaded power extraction set. This power extraction set consists of a dual-frequency dielectric-loaded decelerating structure (decelerator) and two changeable output couplers. In the decelerator, the TM02 mode synchronizes with an ultra-relativistic electron beam at 20.8GHz, and the TM03 mode synchronizes with the beam at 35.1GHz. These frequencies are both harmonics of 1.3GHz, the operating frequency of the electron gun and linac at the Argonne Wakefield Accelerator. The power generated in the unwanted TM01 mode is effectively suppressed for bunch train operation with a novel mode suppression technique. To extract power from the decelerator to standard rectangular waveguides, a TM02-TE10 output coupler was designed with S21 = -0.26dB at 20.8GHz, and a TM03-TE10 output coupler with S21 = -0.66dB at 35.1GHz. 90.4MW and 8.68MW rf power are expected to be extracted from a drive beam with charge of 50nC per bunch, at 20.8GHz and 35.1GHz respectively.