Design and analysis of a dual-band THz metamaterial sensor with high refractive index sensitivity

Abstract

A terahertz metamaterial comprised of an array of cross rectangular split-ring resonators (CRSRR) was proposed and analyzed for sensing applications, and it exhibited two resonances in the frequency range of 0.2–3 THz. The resonant frequencies of different resonant modes were explained using equivalent circuit models. Furthermore, the influence on equivalent capacitance and inductance of the circuit with respect to different geometrical dimensions of the CRSRR structure were analyzed, and the results indicated that the resonant frequencies of the proposed metamaterial can be designed as the desired value by adjusting the CRSRR unit geometry. In addition, the sensing performances of the metamaterial were calculated based on the optimized structure, showing that it had high refractive index sensitivity of 309 and 730 GHz/RIU at two resonant frequencies, respectively. Meanwhile, such ability to operate at two frequency bands enabled the designed sensor could characterize the identical samples at different frequencies, thereby increasing the sensing sensitivity and decreasing the impact of environmental disturbance. Our study opens up new prospects in the design of terahertz metamaterial sensors with high sensitivity in a multi-band range, which is essential to meet increasing needs in terahertz sensing.

Tri-band metasurface absorber based on square rotational symmetry

“…Our design has similar performance compared with the figure of merit are 1.87 and 4.9 sensors designed by Hu et al [31]. In addition, the figure of merit of the sensor designed by Lu et al [32] are 2.97 and 2.25 at two frequency points respectively. And the figure of merit of the single-frequency sensor designed by Wang et al [33] is 3.3.…”

A novel terahertz integrated sensor for liquid samples detections based on metamaterial and embedded microfluidic channels

“…A comparison between the performance of the reported MMs sensors with and without microfluidic techniques with our design in transmission and reflection modes are represented in table 1. By integrating the microfluidic technique with THz MMs, our sensor is capable to complete hydrated samples detections, compared to most conventional THz MMs sensors [29,[32][33][34][35][36][37]. Meanwhile, it can be clearly seen that our sensors show merits in relative high sensitivity, high Q-factors and high FOM compared to most recently published experimental and theoretical results for hydrated samples detections.…”

Graphene-Based Tunable Dual-Frequency Terahertz Sensor

“…The results obtained in this paper are compared with similar works in Refs. [ 26 , 27 , 29 , 34 , 35 , 36 , 37 , 38 ] shown in Table 1 . Compared with Refs.…”

“…Compared with Ref. [ 37 ], the proposed sensor not only has a wider operable frequency band range, higher sensitivity, and higher Q and FOM values but can also be dynamically adjusted by the introduction of graphene. Compared with Refs.…”