Higher-order modes excitation in generator with photonic crystal

• Published in: Results in physics 2019-12, Vol.15, p.102758, Article 102758
• Main Authors: Badarin, Artem A., Kurkin, Semen A., Frolov, Nikita S., Koronovskii, Alexey A., Hramov, Alexander E., Rak, Alexey O.
• Format: Article
• Language: English
• Subjects: Distributed feedback; Electron beam; Higher-order modes; Modes selection; Photonic crystal; Sub-terahertz radiation; Volume free-electron laser
• ISSN: 2211-3797; 2211-3797
• DOI: 10.1016/j.rinp.2019.102758

•Effective selection of high-order modes in volume free electron laser (vFEL) with photonic crystal (PC) is possible due to fine tuning of the emitter configuration.•The regimes, characterized by effective mode selection in vFEL with PC, are accompanied by the complex electron beam dynamics.•The discovered mechanisms are taken as the basis of the approach to essential increasing the generation frequency up to sub-THz range due to the excitation of higher modes. We revealed physical processes responsible for the excitation of higher-order modes in volume free-electron laser with photonic crystal. We discovered the new approach for the selection of the electromagnetic modes in volume free-electron laser with photonic crystal based on the choice of the emitter configuration. This approach allows essential multiplying the generation frequency. We found that the regimes with developed higher-order modes are accompanied by complex squeezed-like beam dynamics. Also, we present the results of the optimization of volume free-electron laser with photonic crystal in terms of excitation of high-order modes. In particular, we investigated the influence of the location of electron beams on the excitation of photonic crystal eigenmodes.