Abstract-Coherent Terahertz Radiation from Multiple Electron Beams Excitation within a Plasmonic Crystal-like structure

• Yaxin Zhang
• , Yucong Zhou
• , Yin Gang
• , Guili Jiang
•  & Ziqiang Yang

http://www.nature.com/articles/srep41116

Coherent terahertz radiation from multiple electron beams excitation within a plasmonic crystal-like structure (a three-dimensional holes array) which is composed of multiple stacked layers with 3 × 3 subwavelength holes array has been proposed in this paper. It has been found that in the structure the electromagnetic fields in each hole can be coupled with one another to construct a composite mode with strong field intensity. Therefore, the multiple electron beams injection can excite and efficiently interact with such mode. Meanwhile, the coupling among the electron beams is taken place during the interaction so that a very strong coherent terahertz radiation with high electron conversion efficiency can be generated. Furthermore, due to the coupling, the starting current density of this mechanism is much lower than that of traditional electron beam-driven terahertz sources. This multi-beam radiation system may provide a favorable way to combine photonics structure with electronics excitation to generate middle, high power terahertz radiation.

Abstract-Coherent terahertz radiation generated from a square-shaped free-electron beam passing through multiple stacked layers with sub-wavelength holes

Yucong Zhou, Yaxin Zhang, Guili Jiang and Zhenhua Wu

http://iopscience.iop.org/0022-3727/48/34/345102/article

zhangyaxin@uestc.edu.cn

Terahertz Science Cooperative Innovation Center, University of Electronic Science and Technology of China, Chengdu 610054, People's Republic of China 

This paper presents terahertz (THz) coherent radiation from the interaction between a square-shaped electron beam and guiding wave mode in a multiple stacked layers with sub-wavelength holes structure. The simulated results show that such a guiding wave mode enhances the field intensity in the electron beam channel so that the interaction is more efficient than the electron beam-surface wave interaction in traditional grating and bi-grating structures. This electron-beam-driven THz source provides a way with much simpler fabrication processes and a larger square size electron beam rather than sheet beam. Furthermore, such a source can be integrated to construct a 2D source-array structure, which demonstrates a good opportunity to generate high power THz radiation.