A high Q terahertz asymmetrically coupled resonator and its sensing performance

Abstract

A terahertz asymmetrically coupled resonator (ACR) consisting of two different split ring resonators (SRRs) was designed. Using finite difference time domain (FDTD), the transmission of ACR and its refractive-index-based sensing performance were simulated and analyzed. Results show that the ACR possesses a sharp coupled transparent peak or high quality factor (Q), its intensity and bandwidth can be easily adjusted by spacing the two SRRs. Furthermore, the resonator exhibits high sensitivity of 75 GHz/RIU and figure of merit (FOM) of 4.4, much higher than the individual SRR sensors. The ACR were fabricated by using laser-induced and chemical non-electrolytic plating with copper on polyimide substrate, the transmission of which measured by terahertz time-domain spectroscopy system is in good agreement with simulations.

Keywords

terahertz / asymmetrically coupled resonator (ACR) / refractive index sensing / high quality factor (Q)

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant No. 61377108).

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg