Coherent and tunable terahertz radiation from graphene surface plasmon polaritons excited by an electron beam

Authors

Shenggang Liu, University of Electronic Science and Technology of China
Chao Zhang, University of WollongongFollow
Min Hu, University of Electronic Science and Technology of China
Xiaoxing Chen, University of Electronic Science and Technology of China
Ping Zhang, University of Electronic Science and Technology of ChinaFollow
Sen Gong, University of Electronic Science and Technology of China
Tao Zhao, University of Electronic Science and Technology of China
Renbin Zhong, University of Electronic Science and Technology of China

RIS ID

90827

Publication Details

Liu, S., Zhang, C., Hu, M., Chen, X., Zhang, P., Gong, S., Zhao, T. & Zhong, R. (2014). Coherent and tunable terahertz radiation from graphene surface plasmon polaritons excited by an electron beam. Applied Physics Letters, 104 (20), 201104-1-201104-5.

Abstract

Although surface plasmon polaritons (SPPs) resonance in graphene can be tuned in the terahertz regime, transforming such SPPs into coherent terahertz radiation has not been achieved. Here, we propose a graphene-based coherent terahertz radiation source with greatly enhanced intensity. The radiation works at room temperature, it is tunable and can cover the whole terahertz regime. The radiation intensity generated with this method is 400 times stronger than that from SPPs at a conventional dielectric or semiconducting surface and is comparable to that from the most advanced photonics source such as a quantum cascade laser. The physical mechanism for this strong radiation is presented. The phase diagrams defining the parameters range for the occurrence of radiation is also shown.