Nature of subpicosecond terahertz pulse propagation in practical dielectric-filled parallel-plate waveguides

A mode-matching analysis of dielectric-filled resonant cavities coupled to terahertz parallel-plate waveguides

“…This analysis can be applied to derive the mode patterns of a partially-filled PPWG by extending the transverse dimension of the rectangular waveguide to infinity. This approach has been previously used to study THz pulse propagation behavior in partially-filled PPWGs [21]. After this extension to the PPWG geometry, the field patterns are described in each region by a set of TE components.…”

High Resolution Waveguide Terahertz Time-Domain Spectroscopy

“…Adding dielectric material to the PPWG effectively increases the gap width, which, in turn, lowers the cut-off frequencies of the higher order modes. For the case of a uniform dielectric film the effect on the PPWG modal properties can be predicted [21,40]. For discontinuous polycrystalline films the situation is more complex.…”

“…A potential solution is to use waveguide geometries which define and guide the beam of sub-ps THz pulses. Here the design of the waveguide can be optimized to control specific properties such as coupling efficiency [18], propagation losses [19], dispersion [20] and modal profile [21]. Even focusing waveguides can be designed [22] to confine THz radiation to well below the diffraction limit [23,24].…”

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

“…Previous studies have demonstrated that the metal parallel-plate waveguide (PPWG) is capable of propagating terahertz pulses [1][2][3][4][5][6]. With no group-velocity dispersion, the transverse electromagnetic (TEM) mode of PPWG is characterized by undistorted and low-loss wave propagation.…”