Terahertz multi-metal-wire hybrid-cladding hollow waveguide for refractive index sensing
Yu Ying-Ying†, , Li Xu-You, He Kun-Peng, Sun Bo
       

Mode field area as a function of measurand refractive index for d1 = 1.5 mm, d2 = 0.49 mm, and f = 0.89 THz.