The effect of shaping the ground plane on the performance of a square loop coplanar waveguide (CPW)-fed printed antenna is reported in this paper. Experimental results are presented on the reflection coefficient and radiation pattern of the investigated antennas. Simulation results are presented on the current distribution, input impedance and gain. It is observed based on the results that shap...

II–IV–N2 wide band gap semiconductors such as ZnSiN2, ZnGeN2, and ZnSiGeN2 have potential uses for nonlinear materials and as lattice matching compounds for the growth of SiC and GaN devices. In this study, the dispersion of the TE and TM indices of refraction has been measured systematically using the prism coupling technique for an orthorhombic ZnSiN2 epitaxial layer grown on r-plane sapphire...

Exact solutions are obtained for all the modes of wave propagation along an anisotropic cylindrical waveguide. Closed-form expressions for the energy flow on the waveguide are also derived. For extremely anisotropic waveguide where the transverse permittivity is negative 0 while the longitudinal permittivity is positive 0 , only transverse magnetic TM and hybrid modes will propagate on the wave...

This paper reviews the progress of the passive optical network, and discusses a viable means for the realisation of future generation agile gigabits passive optical networks, (GPONs) by the use of low cost narrow band tunable lasers and arrayed waveguide gratings (AWGs). It projectes a twostage strategy for the realisation of future generation agile GPONs, i.e., the near-term Time and Wavelengt...

Previously, we have described a low temperature grown GaAs device that uses single-photon absorption to perform a carrier lifetime limited optical autocorrelation of picosecond optical pulses. In this article, we describe how this same device could be used to perform an autocorrelation of femtosecond optical pulses by utilizing two-photon absorption ~TPA!. Furthermore, we propose how to model a...

The coherent interaction between ensembles of helium Rydberg atoms and microwave fields in the vicinity of a solid-state coplanar waveguide is reported. Rydberg-Rydberg transitions, at frequencies between 25 and 38 GHz, have been studied for states with principal quantum numbers in the range 30-35 by selective electric-field ionization. An experimental apparatus cooled to 100 K was used to redu...

We investigate the dynamical Casimir effect in a coplanar waveguide (CPW) terminated by a superconducting quantum interference device (SQUID). Changing the magnetic flux through the SQUID parametrically modulates the boundary condition of the CPW, and thereby, its effective length. Effective boundary velocities comparable to the speed of light in the CPW result in broadband photon generation wh...

A novel method of introducing a notch at a point of high magnetic field in a coplanar waveguide (cpw) radial and diamond stub resonator to increase the quality factor (Q) was analysed. For comparison both radial and diamond shaped cpw resonators with and without notches were fabricated on gallium arsenide (GaAs) semi-insulating substrate at the James Watt Nanofabrication Centre and tested in th...

In this article, a new CAD model for the coplanar waveguide (CPW) cross-over air-bridge is proposed. The model takes into account the CPW open-end capacitance and the vertical strips of the bridge. The section directly underneath the bridge is modeled as a small section of a microstrip line. Our results are in good agreement with the published full-wave results. © 2005 Wiley Periodicals, Inc. I...

Finite width coplanar waveguide (FCPW) transmission line characteristics on semiconductor substrates are presented. It is shown that the ground plane width may be varied to obtain a single mode transmission line without resonances. The variation of the ground plane width has been found to have negligible effect on the loss of the lines. In addition, it is shown that FCPW permits new circuit com...