▎ 摘　　要

Controlling the light transmission in the epsilon-near-zero channel, which is covered by the perfect-electric-conductor (PEC) walls, has been demonstrated in [L. Yang, T. Hu, A. Shen, C. Pei, B. Yang, T. Dai, H. Yu, Y. Li, X. Jiang, and J. Yang, Opt. Lett. 39, 1909 (2014)]. In this work, we investigate the possibility of replacing the PEC by some practical metal materials. Based on it, an ultracompact plasmonic switch with the length of 15 nm is presented. Its highest extinction ratio is more than 13 dB, while the 3-dB extinction ratio is obtained with a 0.41V gate voltage. (C) 2014 AIP Publishing LLC.