Broadside-coupled triangular split-ring-resonators for terahertz sensing

¹ Department of Electrical and Electronics Engineering, Middle East Technical University, Northern Cyprus campus, Kalkanli, Guzelyurt, TRNC, Mersin 10, Turkey
² Johann Wolfgang Goethe-Universität, Physikalisches Institut, Max-von-Laue str. 1, D-60438 Frankfurt am Main, Germany

^a e-mail: sabah@metu.edu.tr

Received: 9 February 2012
Revised: 11 July 2012
Accepted: 11 January 2013
Published online: 8 March 2013

Abstract

In this study, broadside-coupled triangular split-ring-resonators are designed and simulated as THz sensors. Their double-side sensing capability provides sensitivity enhancement compared with singlesided sensors. The material to be detected is modeled as an over-layer on the structure. The ensuing change of the transmission resonances is investigated as a function in the thickness and permittivity of the substrate and of the one- or two-sided over-layer. The propagation direction of the incident wave also allows to select the excited mode (via the polarization of the radiation) which provides additional flexibility to the proposed sensor device by the possibility to operate it over a larger frequency range. Overall, the polarization dependency of the structure, the double-side sensing and the high sensitivity make such structures attractive as THz sensors.