Terahertz time-domain spectroscopy accesses the frequency range between 100 GHz and 5 THz by using the coherent generation and detection based on femtosecond laser sources. On the way to obtain fingerprint absorption spectra of molecular solids, terahertz waveguides have proven to be a valuable tool to extend the results to narrow and high resolution linewidths of crystalline solids. We will di...

The diffraction by a semi-infinite parallel-plate waveguide with sinusoidal wall corrugation is analyzed for the H-polarized plane wave incidence using the Wiener-Hopf technique combined with the perturbation method. Introducing the Fourier transform for the unknown scattered field and applying an approximate boundary condition together with a perturbation series expansion of the scattered fiel...

We demonstrate a 2-D artificial dielectric medium suitable for the terahertz region by exploiting the characteristic frequency dependence in the phase velocity of the lowest order transverse-electric mode of the parallel-plate waveguide (PPWG). This artificial medium exhibits a plasma-like behavior having a frequency-dependent refractive index that varies between zero and unity. Using this medi...

We study 2D-polaritons in an atomically thin dipole-active layer (2D-crystal) placed inside a parallel-plate wavegude, and investigate the possibility to obtain the localized wavegude modes associated with atomic defects. Considering the wavegude width, l, as an adjustable parameter, we show that in the waveguide with l ∼ 10 a, where a is the lattice parameter, the localized mode can be provide...

HICKS, CHRIS WAYNE. Experimental and Electromagnetic Modeling of WaveguideBased Spatial Power Combining Systems. (Under the direction of Michael B. Steer.) Recent technological advancements and demands for high power sources at microwave and millimeter-wave frequencies have initiated extensive theoretical and experimental research in the area of quasi-optical and spatial power combining. The wo...

We experimentally characterize the field confinement properties of various parallel-plate waveguide (PPWG) geometries in the terahertz spectral range. In contrast to infinite-width PPWGs with free-space diffraction along the unshielded direction, finite-width (and also tapered) PPWGs showwell-confined THz fields at the output facet. Both the transverse field component, perpendicular to the insi...

The parallel-plate waveguide (PPWG) has drawn considerable research interest [1–12], since it was first reported to support the undistorted propagation of broadband terahertz (THz) pulses. From that time, the transverse-electromagnetic (TEM) mode of the PPWG has been the popular choice for measurements due to its low loss, ease of quasi-optic coupling, and negligible dispersion as a result of t...

We perform an experimental study of the phase and amplitude of microwaves interacting with and scattered by two-dimensional negative index metamaterials. The measurements are performed in a parallel plate waveguide apparatus at X-band frequencies (8-12 GHz), thus constraining the electromagnetic fields to two dimensions. A detection antenna is fixed to one of the plates, while a second plate wi...