New THZ excitation of planar Goubau line

Abstract

Quite recently, it has been found that conducting wires lying on a flat dielectric substrate can propagate Terahertz (THz) waves in the same way as conducting wires entirely coated with a dielectric (Goubau line). This phenomenon is interesting because it is a basic requirement to fabricate integrated circuits at THz frequencies. The excitation of planar Goubau line (PGL) waves was found to have a very strong Goubau mode on conducting wire. The excitation was made with a coplanar waveguide transition fed with a THz signal obtained from a vector network analyzer. The Goubau mode on PGL was excited with high efficiency (up to 75%.). This is a first step in the design of THz BioMEMS dedicated to living cell investigations. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2998–3001, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23850

Development of planar Goubau line - microfluidic integrated devices for THz spectroscopy of liquid analytes

“…The expected delay for reflections C and Cꞌ was 20.7×10 -12 s, and 22.2×10 -12 s respectively, approximately 10% lower than the measured values. This inaccuracy is likely to be caused by the assumption that the Goubau mode is perfectly circular about the centre conductor, which has been shown to be false through simulation [12]. While a more accurate field distribution can be calculated numerically, this problem is yet to be solved analytically.…”

Terahertz Interferometer for Integrated Goubau-Line Waveguides

“…The exciting signal is provided up to 325 GHz by a Vectorial Network Analyzer (VNA) dedicated to coplanar waveguides (CPW). As a consequence, a CPW/Goubau transition [12] has been used to propagate the Goubau mode. Used PGL are 500 nm-high and 5 µm-wide gold wires deposited on a 350 µm-thick borosilicate glass (Pyrex) substrate.…”

“…Transitions between coplanar waveguides and PGL have been previously reported [12] and sub-wavelength scaled spiralresonators have been proposed in PGL [13]. PGL power dividers are now available [14,15].…”

Terahertz Spiral Planar Goubau Line Rejectors for Biological Characterization

“…In our case, measurements are performed with a Vectorial Network Analyzer (VNA) up to 0.325 THz coupled with coplanar tips. As a consequence, a coplanar-PGL transition has been realized to get a high-efficient Goubau mode excitation (about 75%) [15]. Figure 1 shows the electric field propagation along a 1.5 mm-long and 5 µm-wide line, calculated with the Microwave Studio CST 3D simulation software.…”