Design and optimization of terahertz directional coupler based on hybrid-cladding hollow waveguide with low confinement loss*
Yu Ying-Ying†, Li Xu-You, Sun Bo, He Kun-Peng
       
Dependences of coupling ratio for each low-confinement-loss frequency regime on frequency as t 1 = 0.20 mm, 0.22 mm, 0.24 mm, and t 2 = 0.30 mm.