Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
7.3
3.4
Journals
Sensors
Special Issues
Terahertz Sensors
sensors-logo
Submit to Special Issue Submit Abstract to Special Issue Review for Sensors Propose a Special Issue

Journal Menu

► Journal Menu

Journal Browser

► Journal Browser
share announcement

Terahertz Sensors

A special issue of Sensors (ISSN 1424-8220). This special issue belongs to the section "Optical Sensors".

Deadline for manuscript submissions: 31 May 2025 | Viewed by 4495

Special Issue Editor

Dr. Dongshan Wei

E-Mail Website
Guest Editor
Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
Interests: terahertz spectroscopy; terahertz near-field imaging; metamaterial; opto-electric detection; density functional theory

Special Issue Information

Dear Colleagues,

For most molecular detections in practice, the concentration of samples is often at a trace level and samples cannot adequately interact with the incident THz wave, which results in difficulty in capturing weak changes in the amplitude and phase for conventional terahertz (THz) spectroscopy techniques and limits applications of THz spectroscopy. How to enhance the spectral signal of samples in the THz band becomes a key issue. In the recent decade, a number of spectral signal enhancement techniques, including surface plasmon resonance, quantum dots, metamaterials, and quasi-bound states in the continuum (QBIC), have been utilized to improve the detection sensitivity of THz spectroscopy. Despite these advancements, the limit of detection (LOD) still cannot satisfy the practical demand. Novel THz sensors with higher Q values and sensitivity, better easiness in fabrication, and better stability in utilization are continuously aspired. This Special Issue, therefore, seeks original research and review articles on the design, fabrication, and applications of novel THz sensors for low-concentration or even trace molecular detection in food, agriculture, biomedicine, etc.

Potential topics include, but are not limited to, the following themes:

  • THz sensors: two-dimensional materials, metamaterials, quantum dots, photonic crystals, QBIC, etc.
  • New THz sensing mechanisms and methods.
  • THz sensing with new algorithms.
  • THz sensing applications in new fields.

Dr. Dongshan Wei
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Sensors is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • THz metamaterial
  • THz sensing
  • QBIC
  • quantum dot
  • photonic crystal
  • molecular marker
  • trace detection
  • Q value
  • sensitivity
  • resonant frequency

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (5 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

7 pages, 2029 KiB  
Communication
A Chirped Characteristic-Tunable Terahertz Source for Terahertz Sensing
by Feilong Gao, Mingzhe Jiang and Shaodong Hou
Sensors 2024, 24(16), 5419; https://doi.org/10.3390/s24165419 - 22 Aug 2024
Viewed by 492
Abstract
In broadband terahertz waves generated by femtosecond lasers, spatial chirp will be simultaneously produced with the introduction of angular dispersion. The chirp characteristics of the terahertz wave will directly affect the frequency response, bandwidth response, and intensity response of the terahertz sensor. To [...] Read more.
In broadband terahertz waves generated by femtosecond lasers, spatial chirp will be simultaneously produced with the introduction of angular dispersion. The chirp characteristics of the terahertz wave will directly affect the frequency response, bandwidth response, and intensity response of the terahertz sensor. To enhance the capability of terahertz sensors, it is necessary to control and improve the chirped characteristics of broadband terahertz sources. We generate a chirped terahertz wave via optical rectification in a LiNbO3 prism using the technique of pulse front tilt. The effect of the pump-beam spot size on THz generation is systematically studied. The pump’s spot size is manipulated using a telescope system. With a pump spot diameter of 1.8 mm, the scanning spectrum of the THz pulse is narrower and is divided into multiple distinct peaks. In contrast, using a pump spot diameter of 3.7 mm leads to increased efficiency in the generation of THz pulses. Also, we investigate the underlying properties governing the generation of chirped terahertz pulses using varying pump pulse spot diameters. Full article
(This article belongs to the Special Issue Terahertz Sensors)
►▼ Show Figures

Figure 1

15 pages, 5972 KiB  
Article
Design and Numerical Modeling of Terahertz Metasurface with Dual Functions of Sensing and Filtering
by Lu Zhang, Huayan Sun, Zhe Chen, Runfeng Tang, Jinxiao Yang and Weilin Li
Sensors 2024, 24(15), 4823; https://doi.org/10.3390/s24154823 - 25 Jul 2024
Viewed by 515
Abstract
This study proposes a dual-functional terahertz device based on the Dirac semimetal, serving as both a sensing element and a band-pass filter. The device’s operating mode can switch between these two functions by utilizing the phase transition property of vanadium dioxide (VO2 [...] Read more.
This study proposes a dual-functional terahertz device based on the Dirac semimetal, serving as both a sensing element and a band-pass filter. The device’s operating mode can switch between these two functions by utilizing the phase transition property of vanadium dioxide (VO2). When VO2 is in the insulating state, the device functions as a sensing element. The simulation results demonstrate an impressive refractive index sensitivity of 374.40 GHz/RIU (Refractive Index Unit). When VO2 is in the metallic state, the device functions as a band-pass filter, exhibiting a center frequency of 2.01 THz and a 3 dB fractional bandwidth of 0.91 THz. The integration of these dual functionalities within a single terahertz device enhances its utility in both sensing and filtering applications. Full article
(This article belongs to the Special Issue Terahertz Sensors)
►▼ Show Figures

Figure 1

13 pages, 4802 KiB  
Article
Terahertz Sensing of L-Valine and L-Phenylalanine Solutions
by Jingyi Shu, Xinli Zhou, Jixuan Hao, Haochen Zhao, Mingming An, Yichen Zhang and Guozhong Zhao
Sensors 2024, 24(12), 3798; https://doi.org/10.3390/s24123798 - 12 Jun 2024
Cited by 1 | Viewed by 631
Abstract
To detect and differentiate two essential amino acids (L-Valine and L-Phenylalanine) in the human body, a novel asymmetrically folded dual-aperture metal ring terahertz metasurface sensor was designed. A solvent mixture of water and glycerol with a volume ratio of 2:8 was proposed to [...] Read more.
To detect and differentiate two essential amino acids (L-Valine and L-Phenylalanine) in the human body, a novel asymmetrically folded dual-aperture metal ring terahertz metasurface sensor was designed. A solvent mixture of water and glycerol with a volume ratio of 2:8 was proposed to reduce the absorption of terahertz waves by reducing the water content. A sample chamber with a controlled liquid thickness of 15 μm was fabricated. And a terahertz time-domain spectroscopy (THz-TDS) system, which is capable of horizontally positioning the samples, was assembled. The results of the sensing test revealed that as the concentration of valine solution varied from 0 to 20 mmol/L, the sensing resonance peak shifted from 1.39 THz to 1.58 THz with a concentration sensitivity of 9.98 GHz/mmol∗L−1. The resonance peak shift phenomenon in phenylalanine solution was less apparent. It is assumed that the coupling enhancement between the absorption peak position of solutes in the solution and the sensing peak position amplified the terahertz localized electric field resonance, which resulted in the increase in frequency shift. Therefore, it could be shown that the sensor has capabilities in performing the marker sensing detection of L-Valine. Full article
(This article belongs to the Special Issue Terahertz Sensors)
►▼ Show Figures

Figure 1

11 pages, 3550 KiB  
Article
Detection of Low-Concentration Biological Samples Based on a QBIC Terahertz Metamaterial Sensor
by Bing Dong, Bo Wei, Dongshan Wei, Zhilin Ke and Dongxiong Ling
Sensors 2024, 24(11), 3649; https://doi.org/10.3390/s24113649 - 4 Jun 2024
Viewed by 955
Abstract
Quasi-bound state in the continuum (QBIC) can effectively enhance the interaction of terahertz (THz) wave with matter due to the tunable high-Q property, which has a strong potential application in the detection of low-concentration biological samples in the THz band. In this paper, [...] Read more.
Quasi-bound state in the continuum (QBIC) can effectively enhance the interaction of terahertz (THz) wave with matter due to the tunable high-Q property, which has a strong potential application in the detection of low-concentration biological samples in the THz band. In this paper, a novel THz metamaterial sensor with a double-chain-separated resonant cavity structure based on QBIC is designed and fabricated. The process of excitation of the QBIC mode is verified and the structural parameters are optimized after considering the ohmic loss by simulations. The simulated refractive index sensitivity of the sensor is up to 544 GHz/RIU, much higher than those of recently reported THz metamaterial sensors. The sensitivity of the proposed metamaterial sensor is confirmed in an experiment by detecting low-concentration lithium citrate (LC) and bovine serum albumin (BSA) solutions. The limits of detection (LoDs) are obtained to be 0.0025 mg/mL (12 μM) for LC and 0.03125 mg/mL (0.47 μM) for BSA, respectively, both of which excel over most of the reported results in previous studies. These results indicate that the proposed THz metamaterial sensor has excellent sensing performances and can well be applied to the detection of low-concentration biological samples. Full article
(This article belongs to the Special Issue Terahertz Sensors)
►▼ Show Figures

Figure 1

13 pages, 2623 KiB  
Article
Tunable High-Sensitivity Four-Frequency Refractive Index Sensor Based on Graphene Metamaterial
by Xu Bao, Shujun Yu, Wenqiang Lu, Zhiqiang Hao, Zao Yi, Shubo Cheng, Bin Tang, Jianguo Zhang, Chaojun Tang and Yougen Yi
Sensors 2024, 24(8), 2658; https://doi.org/10.3390/s24082658 - 22 Apr 2024
Viewed by 1122
Abstract
As graphene-related technology advances, the benefits of graphene metamaterials become more apparent. In this study, a surface-isolated exciton-based absorber is built by running relevant simulations on graphene, which can achieve more than 98% perfect absorption at multiple frequencies in the MWIR (MediumWavelength Infra-Red [...] Read more.
As graphene-related technology advances, the benefits of graphene metamaterials become more apparent. In this study, a surface-isolated exciton-based absorber is built by running relevant simulations on graphene, which can achieve more than 98% perfect absorption at multiple frequencies in the MWIR (MediumWavelength Infra-Red (MWIR) band as compared to the typical absorber. The absorber consists of three layers: the bottom layer is gold, the middle layer is dielectric, and the top layer is patterned with graphene. Tunability was achieved by electrically altering graphene’s Fermi energy, hence the position of the absorption peak. The influence of graphene’s relaxation time on the sensor is discussed. Due to the symmetry of its structure, different angles of light source incidence have little effect on the absorption rate, leading to polarization insensitivity, especially for TE waves, and this absorber has polarization insensitivity at ultra-wide-angle degrees. The sensor is characterized by its tunability, polarisation insensitivity, and high sensitivity, with a sensitivity of up to 21.60 THz/refractive index unit (RIU). This paper demonstrates the feasibility of the multi-frequency sensor and provides a theoretical basis for the realization of the multi-frequency sensor. This makes it possible to apply it to high-sensitivity sensors. Full article
(This article belongs to the Special Issue Terahertz Sensors)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-5
Back to TopTop