Investigation of Transmission Losses in a Dielectric Slab Waveguide at Terahertz Frequencies

In this paper, a theoretical analysis of transmission losses for the TE, TM modes of a dielectric slab waveguide at terahertz frequencies is performed. Equations are presented for the field components, dispersion characteristics, core power confinement factor and attenuation constant as a function of the operating frequencies, waveguide dimensions and material constants. The calculation curves covering frequencies and dimensions for the given material constants in the THz region are presented. The investigation results show that, the loss of the slab waveguide increases at a rate proportional to approximately f, which is much slower than that of rectangular metallic waveguide and the microstrip line at a rate proportional to approximately f^3/2. By selecting proper dimensions and dielectric materials, the dielectric slab waveguide can be used to guide THz wave efficiently with high power confinement. These properties may have some potential applications in the THz regime.