[21a-P6-1~17] 3.9 Terahertz technologies

[21a-P6-7] Cherenkov free-electron laser with negative-index materials

〇Dazhi Li¹, Keisuke Takano², Makoto Nakajima², Shuji Miyamoto³ (1.ILT, 2.ILE, 3.Hyogo Univ.)

Keywords:metamaterial,free-electron laser

We present an analysis of a Cherenkov free-electron laser based on a single slab made from negative-index materials. A flat electron beam with finite thickness travelling close to the surface of the slab interacts with the copropagating electromagnetic surface mode. Under suitable conditions there is inherent feedback in such a scheme due to the characteristics of negative-index materials, which means that the system can oscillate without external reflectors when the beam current exceeds a threshold value.