Terahertz demonstrations of effectively two-dimensional photonic bandgap structures

Abstract

We demonstrate effectively two-dimensional (2D) terahertz (THz) photonic bandgap (PBG) structures for transverse electromagnetic (TEM) mode propagation within metal parallel plate waveguides (PPWG). The 2D-PBG structures consisting of square arrays of dielectric cylinders were characterized by THz time-domain spectroscopy (THz-TDS). THz photonic bandgaps were observed, as determined by the 160 mum lattice constant, the 65 mum diameter, and the dielectric constant of the cylinders. The experimental measurements were fitted with excellent agreement to 2D theory, confirming that for TEM mode propagation, effectively 2D propagation experiments can be achieved within the bounded space of the PPWG.

Dynamic optically induced planar terahertz quasioptics

“…6 By incorporating 2D quasioptics between the plates, pulses can be manipulated in the plane just as in free space as the transverse electromagnetic ͑TEM͒ mode has no spatial dependence perpendicular to the plates. 11 Reflective, 11 refractive, and diffractive quasioptical elements 12 have been demonstrated as well as 2D photonic crystal lattices, 13,14 waveguides, 9 and resonators. 15 These passive components form the basic structure of a THz photonic circuit, all on a chip.…”

Modal Analysis of Metal-Stub Photonic Band Gap Structures in a Parallel-Plate Waveguide

“…With no group-velocity dispersion, the transverse electromagnetic (TEM) mode of PPWG is characterized by undistorted and low-loss wave propagation. The two-dimensional (2D) PBG [7] structure is also brought up many applications in terahertz range, most using full metal or dielectric cylinders/holes [8][9][10][11][12]. Using dielectric cylinders or holes must consider their dielectric properties and frequency response, while using full metal cylinders generally has an extremely low transmission [13,14].…”

Metallic photonic crystals for terahertz tunable filters

“…For the construction of compact application systems, THz functional devices such as THz switches [5], filters [6], splitters [7] and phase retarders [8] are indispensable. Among these devices, photonic crystals (PCs) have proved to be an effective way to transmit and control THz waves [9][10][11]. PCs for high quality switching and filtering have been widely studied due to their potential applications [12][13][14].…”