Sensors

Journal Browser

► Journal Browser

Terahertz and Millimeter Wave Sensing and Applications (Volume II)

Share This Special Issue

Special Issue Editors

Special Issue Information

Dear Colleagues,

We are happy to launch this follow-up MDPI Special Issue on "Terahertz and Millimeter Wave Sensing and Applications (Volume II)". Thanks to the many valuable submissions to our previous Special Issue (“Terahertz and Millimeter Wave Sensing and Applications”; link here: https://www.mdpi.com/journal/sensors/special_issues/TMWSA), we could already present some recent developments in the field of terahertz- and millimeter-wave technologies. In particular, these technologies are continuously receiving attention in many fields of industrial and scientific applications. Ongoing developments of terahertz- and millimeter-wave sources, detectors, sensors, and measurement techniques have led to technological readiness for integration in modern industrial processes, for quality inspection, and for materials science and characterization. Many applications can be summarized under the general term “non-destructive testing” (NDT), where terahertz- and millimeter-wave technologies can reveal their unique potential. These contact-free, safe, and easy-to-use technologies can address many of today’s challenges in industrial production, maintenance, quality inspection, and materials research, replacing or complementing well-established NDT technologies in these areas. On the other hand, the field of terahertz- and millimeter-wave sensing addresses, e.g., gas spectroscopy, biomedical applications, monitoring of ultrafast dynamics, and many more.

In this Special Issue, we encourage authors from all fields of research and development related to terahertz- and millimeter-wave sensing and applications, with both industrial and scientific backgrounds, to submit original manuscripts with a focus on, but not limited to, practical industrial and/or scientific applications:

- New fields of terahertz applications and sensing;
- Non-destructive testing (NDT);
- Terahertz- and millimeter-wave imaging;
- Terahertz measurements and systems;
- Terahertz sources, detectors, and sensors.

Dr. Maris Bauer
Dr. Fabian Friederich
Guest Editors

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

new fields of terahertz applications and sensing
non-destructive testing (NDT)
terahertz- and millimeter-wave imaging
terahertz measurements and systems
terahertz sources, detectors, and sensors

Published Papers (2 papers)

Download All Papers

Research

11 pages, 19094 KiB

Open AccessArticle

Narrowband Thermal Terahertz Emission from Homoepitaxial GaAs Structures Coupled with Ti/Au Metasurface

by Ignas Grigelionis, Vladislovas Čižas, Mindaugas Karaliūnas, Vytautas Jakštas, Kȩstutis Ikamas, Andrzej Urbanowicz, Marius Treideris, Andrius Bičiūnas, Domas Jokubauskis, Renata Butkutė and Linas Minkevičius

Sensors 2023, 23(10), 4600; https://doi.org/10.3390/s23104600 - 9 May 2023

Cited by 2 | Viewed by 1399

Abstract

We report on the experimental evidence of thermal terahertz (THz) emission tailored by magnetic polariton (MP) excitations in entirely GaAs-based structures equipped with metasurfaces. The n-GaAs/GaAs/TiAu structure was optimized using finite-difference time-domain (FDTD) simulations for the resonant MP excitations in the frequency range below 2 THz. Molecular beam epitaxy was used to grow the GaAs layer on the n-GaAs substrate, and a metasurface, comprising periodic TiAu squares, was formed on the top surface using UV laser lithography. The structures exhibited resonant reflectivity dips at room temperature and emissivity peaks at

T = 390

°C in the range from 0.7 THz to 1.3 THz, depending on the size of the square metacells. In addition, the excitations of the third harmonic were observed. The bandwidth was measured as narrow as 0.19 THz of the resonant emission line at 0.71 THz for a 42 μm metacell side length. An equivalent

L C

circuit model was used to describe the spectral positions of MP resonances analytically. Good agreement was achieved among the results of simulations, room temperature reflection measurements, thermal emission experiments, and equivalent

L C

circuit model calculations. Thermal emitters are mostly produced using a metal-insulator-metal (MIM) stack, whereas our proposed employment of n-GaAs substrate instead of metal film allows us to integrate the emitter with other GaAs optoelectronic devices. The MP resonance quality factors obtained at elevated temperatures (

Q \approx 3.3 to 5.2

) are very similar to those of MIM structures as well as to 2D plasmon resonance quality at cryogenic temperatures. Full article

(This article belongs to the Special Issue Terahertz and Millimeter Wave Sensing and Applications (Volume II))

► Show Figures

Figure 1

12 pages, 12798 KiB

Open AccessArticle

Terahertz Cross-Correlation Spectroscopy and Imaging of Large-Area Graphene

by Bjørn Hübschmann Mølvig, Thorsten Bæk, Jie Ji, Peter Bøggild, Simon Jappe Lange and Peter Uhd Jepsen

Sensors 2023, 23(6), 3297; https://doi.org/10.3390/s23063297 - 21 Mar 2023

Cited by 7 | Viewed by 1764

Abstract

We demonstrate the use of a novel, integrated THz system to obtain time-domain signals for spectroscopy in the 0.1–1.4 THz range. The system employs THz generation in a photomixing antenna excited by a broadband amplified spontaneous emission (ASE) light source and THz detection with a photoconductive antenna by coherent cross-correlation sampling. We benchmark the performance of our system against a state-of-the-art femtosecond-based THz time-domain spectroscopy system in terms of mapping and imaging of the sheet conductivity of large-area graphene grown by chemical vapor deposition (CVD) and transferred to a PET polymer substrate. We propose to integrate the algorithm for the extraction of the sheet conductivity with the data acquisition, thereby enabling true in-line monitoring capability of the system for integration in graphene production facilities. Full article

(This article belongs to the Special Issue Terahertz and Millimeter Wave Sensing and Applications (Volume II))

► Show Figures

Figure 1

Journal Menu

Journal Browser

Terahertz and Millimeter Wave Sensing and Applications (Volume II)

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (2 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI