Dual-mode rf cavity: design, tuning and performance

We present the design and characterization of a dual-mode radiofrequency (rf) cavity, a novel electromagnetic structure with potential benefits such as compactness, efficiency, cost reduction and multifunctionality. The cavity was designed to balance the dual-mode structure considering several factors, such as mode frequencies, quality factor (Q-factor), and minimizing cross talk between couplers. We preformed various tests to verify that this cavity preformed as expected compared to simulated results. As exampled here, a combination of the the fundamental mode TM 010 and the TM 011 mode, tuned to a harmonic of the fundamental, was realized to linearize the off-crest electric field, thereby enabling concurrent bunching and acceleration of charged particle (e.g. electrons) beam in high power systems. The reduction in the number of cavities required to bunch and accelerate promises cost and space savings over conventional approaches. This research lays the foundation for further exploration of multi-mode cavity applications and optimization for specific use cases, with potential implications for a wide range of fields including quantum information platforms.