Abstract-Ultrasensitive sensing with three-dimensional terahertz metamaterial absorber

Siyu Tan, Fengping Yan, Wei Wang, Hong Zhou, Yafei Hou,

http://iopscience.iop.org/article/10.1088/2040-8986/aab66e/pdf

Planar metasurfaces and metamaterial absorbers have shown great promise for label-free sensing applications at microwaves, optical and terahertz frequencies. The realization of high-quality-factor resonance in these structures is of significant interest to enhance the sensing sensitivities to detect the minute frequency shifts. We propose and demonstrate in this manuscript an ultrasensitive terahertz metamaterial absorber sensor based on three-dimensional split ring resonator absorber with a high quality factor of 60.09. The sensing performance of the proposed absorber sensor was systematically investigated through detailed numerical calculations and a maximum refractive index sensitivity of 34.40% RIU-1 was obtained. Furthermore, the absorber sensor can maintain a high sensitivity for a wide range of incidence angles up to 60° under TM polarization incidence. These findings would improve the design flexibility of the absorber sensors and further open up new avenues to achieve ultrasensitive sensing in terahertz regime.
© 2018 IOP Publishing Ltd

Abstract-Polarization Control in Terahertz Metasurfaces with the Lowest Order Rotational Symmetry

1. Longqing Cong^1,2, 
2. Ningning Xu³, 
3. Weili Zhang³ and
4. Ranjan Singh^1,2,*

Article first published online: 28 APR 2015

DOI: 10.1002/adom.201500100

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

http://onlinelibrary.wiley.com/doi/10.1002/adom.201500100/abstract;jsessionid=AFB93DFA086814406112936226B0A4C0.f03t03?deniedAccessCustomisedMessage=&userIsAuthenticated=false

A planar metamolecule with twofold rotational symmetry that shows giant cross polarization transmission leads to strong optical activity and behaves as a perfect circular polarizer. Such planar meta­surfaces would be used to design active polarization control devices and high efficiency wave deflector by carefully engineering the phase discontinuities for real applications in optical and terahertz technologies.