Flexible terahertz Metamaterial sensor for sensitive detection of imidacloprid

Lang, Tingting; Zhang, JinHui; Qiu, Yanqing; Hong, Zhi; Li, Jianjun

doi:10.1016/j.optcom.2023.129430

Cited by 19 publications

(1 citation statement)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among them, since the absorption peak of narrow-band absorption is often generated by resonance, it is easy to relate the frequency of the absorption peak to the external environment. This natural advantage can be exploited in applications such as sensing and detection [ 24 , 25 , 26 ], as well as broadband absorption, because it has irreplaceable advantages over traditional materials in terms of thickness, weight, etc. Therefore, it has a wide range of applications in various applications, including electromagnetic shielding, electromagnetic pollution prevention, multiplexing technology, and so on.…”

Section: Introductionmentioning

confidence: 99%

A Liquid Crystal-Modulated Metastructure Sensor for Biosensing

Liao

Chen

et al. 2023

Sensors

View full text Add to dashboard Cite

In this paper, a liquid crystal-modulated metastructure sensor (MS) is proposed that can detect the refractive index (RI) of a liquid and change the detection range under different applied voltages. The regulation of the detection range is based on the different bias states of the liquid crystal at different voltages. By changing the sample in the cavity that is to be detected, the overall electromagnetic characteristics of the device in the resonant state are modified, thus changing the position of the absorption peaks so that different RI correspond to different absorption peaks, and finally realizing the sensing detection. The refractive index unit is denoted as RIU. The range of the refractive index detection is 1.414–2.828 and 2.121–3.464, and the corresponding absorption peak variation range is 0.8485–1.028 THz and 0.7295–0.8328 THz, with a sensitivity of 123.8 GHz/RIU and 75.6 GHz/RIU, respectively. In addition, an approach to optimizing resonant absorption peaks is explored, which can suppress unwanted absorption generated during the design process by analyzing the energy distribution and directing the current flow on the substrate. Four variables that have a more obvious impact on performance are listed, and the selection and change trend of the numerical values are focused on, fully considering the errors that may be caused by manufacturing and actual use. At the same time, the incident angle and polarization angle are also included in the considered range, and the device shows good stability at these angles. Finally, the influence of the number of resonant rings on the sensing performance is also discussed, and its conclusion has guiding value for optimizing the sensing demand. This new liquid crystal-modulated MS has the advantages of a small size and high sensitivity and is expected to be used for bio-detection, sensing, and so on. All results in this work were obtained with the aid of simulations based on the finite element method.

show abstract

Section: Introductionmentioning

confidence: 99%

A Liquid Crystal-Modulated Metastructure Sensor for Biosensing

Liao

Chen

et al. 2023

Sensors

View full text Add to dashboard Cite

show abstract

Terahertz Sensing Based on Floating Bilayer Metasurface with Toroidal Dipole Resonance Toward Ultra‐High Sensitivity

Liu,

Xiao,

Qin

2024

Advanced Optical Materials

View full text Add to dashboard Cite

Metasurface structures have proven to be effective in enhancing terahertz sensing signals and can thus be used as sensors to improve terahertz detection sensitivity. However, the sensitivity is limited by the poor spatial overlap between the analytes and the local electric field of the metasurface. In this work, a novel design of a floating bilayer metasurface structure for terahertz sensing is proposed and investigated. This structure supports a sharp toroidal dipole resonance and can concentrate near‐field energy on the analyte and metal atoms rather than on the substrate surface by floating the metal atoms. Consequently, the sensitivity is significantly improved to as high as 362 GHz RIU−1; theoretically, this is approximately 2.6 times higher than that of the common metasurface. The ability of the floating bilayer metasurface to quantitatively detect chlorothalonil is experimentally demonstrated. The resonance peak shows a significant frequency shift of 7 GHz for a change of 0.0001 mg dL−1 in chlorothalonil concentration, reaching up to 86 GHz when the change in chlorothalonil concentration is 100 mg dL−1; this is approximately 6.6 times higher than that of the common metasurface. This work provides opportunities for metasurface to realize ultrasensitive sensing in the terahertz regime.

show abstract