基于超材料的自由电子辐射研究进展

Research progress of free-electron radiation based on metamaterials

自由电子与周围电磁环境互作用时可以通过不同的形式辐射电磁波。超材料是一种人工复合材料,可实现传统自然材料所不具备的电磁特性。基于超材料与自由电子之间的相互作用可以打破传统电磁辐射系统的限制,实现对辐射电磁波的极化、相位、波前等特性的灵活操控,这为发展新型的自由电子辐射器件提供了新思路。本文简单介绍了切伦科夫辐射、史密斯-珀塞尔辐射的产生机理,重点回顾了基于超材料的自由电子辐射的最新研究进展,并对未来的技术发展方向进行了展望。

Various types of electromagnetic radiation can be stimulated by free electrons interact with the local electromagnetic environment.Metamaterial is a kind of artificial material,which can achieve unique characteristics that natural material cannot realize.Based on the interaction between the metamaterial and free electron,the radiation characteristics can be flexibly manipulated such as polarization,phase and wavefront,and so on.The related study provides a novel platform for developing novel free-electron radiation devices.This paper briefly introduces the physical mechanism of Cherenkov radiation and Smith-Purcell radiation.Then,the state-of-art of free-electron radiation in metamaterials is introduced.Finally,an outlook of potential research directions for this vigorous realm is provided.