Design of Two-Dimensional Low-Dielectric Photonic Crystal and Its Terahertz Waveguide Application

We have systematically investigated the band structure of a two-dimensional photonic crystal (PC) made of a low permittivity dielectric. We present design of PCs showing photonic band gaps. Subsequently, we propose a terahertz (THz) low-dielectric PC slab waveguide sandwiched between two parallel metal plates. The THz wave propagation on the device was simulated by a finite-difference time-domain method. Taking into account the THz absorption of dielectric and the finite electrical conductivity of the metal, we estimated the propagation loss of a guided mode on the PC slab waveguide. We obtained lower propagation loss than those of typical THz-transmission-lines. (c) 2012 The Japan Society of Applied Physics