Abstract-Multi-band terahertz metamaterial absorber for sensing application

Yuan Yao, Shaopeng Li, Lei Zhu, Fengmin Wu, Xunjun He,  Jiuxing JiangYu

https://www.tandfonline.com/doi/abs/10.1080/10584587.2018.1457352?journalCode=ginf20

In this paper, we proposed a multi-band metamaterial absorber for sensing thin film, which consists of tri-layer structure: patterned multi-split electric ring resonators layer, dielectric spacer layer, and continuous metal ground layer. The calculated results demonstrated that the absorber can exhibit three distinctive absorption peaks with narrow bandwidth. As the surface of the absorber was coated with the analyte layer, moreover, the locations of three absorption peaks appear obvious redshift, and the corresponding maximal sensitivities are 0.119 THz/RIU, 0.248 THz/RIU, and 0.662 THz/RIU, respectively. Therefore, the proposed absorber has significant potential applications in detecting and sensing.

Abstract-Dynamically controlled electromagnetically induced transparency in terahertz graphene metamaterial for modulation and slow light applications

Xunjun He, Yuan Yao, Xingyu Yang, Guangjun Lu, Wenlong Yang, Yuqiang Yang, Fengmin Wu, Zhigang Yu, Jiuxing Jiang,

http://www.sciencedirect.com/science/article/pii/S0030401817307745

By patterning two graphene resonators on a SiO₂/Si substrate, a dynamically controlled electromagnetically induced transparency (EIT) in the terahertz graphene metamaterial was numerically studied through tuning the structural parameter and Fermi energy of graphene. The calculated surface current distributions demonstrate that the distinct EIT window in the graphene metamaterial results from the near-field coupling of two graphene resonators. Moreover, the EIT window can be actively controlled by tuning Fermi energy combined states of two resonators. When the Fermi energy combined state of two resonators changes from (0.21 and 0.16 eV) to (0.4 and 0.11 eV), the amplitude modulation depth of the EIT peak is 97.8% at 0.45 THz, and the corresponding enhanced factor of group delay with 6 times is obtained. This study offers an alternative tuning method to existing optical, thermal, and relative distance tuning, delivering a promising potential for designing active and miniaturized THz devices.

Abstract-Tunable ultrasensitive terahertz sensor based on complementary graphene metamaterials

Xunjun He,   Qingfei Zhang,   Guangjun Lu,   Guobing Ying,  Fengmin Wu and   Jiuxing Jiang  

RSC Adv., 2016, Accepted Manuscript

DOI: 10.1039/C5RA21974D
Received 11 Mar 2016, Accepted 12 May 2016
First published online 23 May 2016
http://pubs.rsc.org/en/Content/ArticleLanding/2016/RA/C5RA21974D?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2Fra+%28RSC+-+RSC+Adv.+latest+articles%29#!divAbstract

In this paper, we propose an ultrasensitive terahertz sensor based on the complementary graphene metamaterial composed of wire-slot and split-ring resonator slot array structure. The destructive interference between two resonators gives rise to a reflection peak enabling ultrasensitive sensing, and sensitivity of 177.7GHz/RIU and FOM of 59.3 can be obtained for the proposed sensor. More importantly, this sensor can not only enhance the absorption of biomelecules and sensing performance, but also dynamically tune the sensing range by shifting the Fermi energy. In addition, the influences of the lateral displacement on the sensing performance are also investigated to improve the sensitivity of sensor. Therefore, this method opens up opportunities for efficiently sensing several organic, explosive, and biomolecules.