Fang, M;    Niu, K;    Huang, Z;    Sha, WEI;    Wu, X;    Koschny, T;    Soukoulis, CM;      (2018)    Investigation of broadband terahertz generation from metasurface.                   Optics Express , 26  (11)   pp. 14241-14250.    10.1364/OE.26.014241 <https://doi.org/10.1364/OE.26.014241>.       Green open access