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arXiv · 2508.10863

Double-Corrugated Degenerate Band-Edge Oscillator Driven by an Electron Beam

Miguel Saavedra-Melo·Robert Marosi·Nelson Castro·Eva Rajo-Iglesias·Filippo Capolino
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Abstract

The properties of a degenerate band-edge (DBE) oscillator based on the synchronous interaction between a linear electron beam synchronized with four degenerate electromagnetic modes are presented. The DBE in the cold slow-wave structure is implemented in a rectangular waveguide with a staggered double corrugation in it. At the DBE, four modes coalesce into a single degenerate mode, forming a very flat dispersion diagram with vanishing or very small group velocity. The DBE oscillator frequency is robust to variations in electron beam current, electrons' velocity, and cavity length. The DBE oscillator concept provided here is expected to be extendable to several other geometries as long as the slow wave structure supports a DBE.

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Miguel Saavedra-Melo, Robert Marosi, Nelson Castro, Eva Rajo-Iglesias, Filippo Capolino. 2025-08-14. Double-Corrugated Degenerate Band-Edge Oscillator Driven by an Electron Beam. https://arxiv.org/abs/2508.10863

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