High-Sensitivity Terahertz Refractive Index Sensor in a Multilayered Structure with Graphene
Jiao Tang,
Yunyang Ye,
Jiao Xu,
Zhiwei Zheng,
Xiangliang Jin,
Leyong Jiang,
Jie Jiang,
Yuanjiang Xiang
Affiliations
Jiao Tang
School of Physics and Electronics, Hunan Normal University, Changsha 410081, China
Yunyang Ye
School of Physics and Electronics, Hunan Normal University, Changsha 410081, China
Jiao Xu
School of Physics and Electronics, Hunan Normal University, Changsha 410081, China
Zhiwei Zheng
School of Physics and Electronics, Hunan Normal University, Changsha 410081, China
Xiangliang Jin
School of Physics and Electronics, Hunan Normal University, Changsha 410081, China
Leyong Jiang
School of Physics and Electronics, Hunan Normal University, Changsha 410081, China
Jie Jiang
Hunan Key Laboratory of Super Microstructure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha 410083, China
Yuanjiang Xiang
School of Physics and Electronics, Hunan University, Changsha 410082, China
In this paper, we propose a high-sensitivity optical sensor at terahertz frequencies based on a composite structure containing a one-dimensional photonic crystal (1D PC) coated with a layer of monolayer graphene. Between the 1D PC and the graphene there is a sensing medium. This high-sensitivity phenomenon originates from the excitation of optical resonance between the graphene and the 1D PC. The proposed sensor is highly sensitive to the Fermi energy of graphene, the thickness and refractive index of the sensing medium, and the number of graphene layers. By selecting appropriate parameters, the maximum sensitivity ( 407.36 ∘ / RIU ) is obtained. We believe the proposed configuration is promising for fabricating graphene-based biosensor- or gas-sensor devices and other related applications in the terahertz band.
