National Key Laboratory of Science and Technology on Vacuum Electronics in Chengdu, Institute of High Energy Electronics, School of Physical Electronics, University of Electronic Science and Technology of China, No. 4, Section 2, North Jianshe Road, Chengdu 610054, China.
School of Electronic Engineering and Computer Science, Queen Mary, University of London, London E1 4NS, UK.
Nat Commun. 2017 Mar 23;8:14901. doi: 10.1038/ncomms14901.
Reversed Cherenkov radiation is the exotic electromagnetic radiation that is emitted in the opposite direction of moving charged particles in a left-handed material. Reversed Cherenkov radiation has not previously been observed, mainly due to the absence of both suitable all-metal left-handed materials for beam transport and suitable couplers for extracting the reversed Cherenkov radiation signal. In this paper, we develop an all-metal metamaterial, consisting of a square waveguide loaded with complementary electric split ring resonators. We demonstrate that this metamaterial exhibits a left-handed behaviour, and we directly observe the Cherenkov radiation emitted predominantly near the opposite direction to the movement of a single sheet electron beam bunch in the experiment. These observations confirm the reversed behaviour of Cherenkov radiation. The reversed Cherenkov radiation has many possible applications, such as novel vacuum electronic devices, particle detectors, accelerators and new types of plasmonic couplers.
反切伦科夫辐射是一种奇特的电磁辐射，它在左手材料中沿运动带电粒子的相反方向发射。反切伦科夫辐射以前从未被观测到，主要是因为缺乏适合束流传输的全金属左手材料和用于提取反切伦科夫辐射信号的合适耦合器。在本文中，我们开发了一种全金属超材料，它由一个加载互补电分裂环谐振器的方波导组成。我们证明了这种超材料表现出左手行为，并在实验中直接观察到单个电子束在运动的相反方向附近主要发射的切伦科夫辐射。这些观察结果证实了切伦科夫辐射的反向行为。反切伦科夫辐射有许多可能的应用，如新型真空电子器件、粒子探测器、加速器和新型等离子体耦合器。
