State-of-the-Art Terahertz Science and Technology II

Dear Colleagues,

You are cordially invited to submit your original research or review articles to this Special Issue on "THz Science and Technology" in Applied Sciences.

This Special Issue is dedicated to all scientific research concerning terahertz radiation: from applications of great interest that exploit the properties of this radiation (spectroscopy, communication, imaging, etc.) to the technological development of the various sources (PCA, QCL, etc.) and detectors (bolometers, PCA, etc.) or detection schemes which can be adopted in various different configurations

The scientific interest in THz radiation (0.3–5 THz) derives from the many optical properties that many materials exhibit at these frequencies. That is, THz is sensitive to polar molecules such as water, but at the same time interacts only very weakly with material composed of non-polar molecules such as plastic and ceramic, and is reflected by most metals. It is less affected by scattering from atmospheric particulates compared to shorter-wavelength radiation, and at these frequencies many molecules have their fingerprints due to roto-vibrational motion, collective modes in crystal lattices, etc.

Some specific topics include:

1) Physics/engineering science for the characterization of new materials to fulfill the increasing needs for electronics and photonics; security applications such as drug, weapon, and explosives recognition. Moreover, THz technology meets the 5G WCS network capacity requirements and is an appealing solution for emerging indoor short-range applications. As a consequence, the design, characterization, and fabrication of protection systems against THz electromagnetic (EM) interference have become subjects of EM compatibility research.

2) Biomedicine: the weak interactions including hydrogen and van der Waals bonds can be probed by THz spectroscopy. Moreover, due to its sensitivity to water, THz can monitor the hydration level, allowing the differentiation between normal and cancer tissues and the assessment of the living state of bacteria, and thanks to its non-ionizing properties is suitable for medical in vivo diagnosis without being harmful for the patient.

3) Climate and Environment: THz is of great interest for monitoring soil, water, and air pollutants.

4) Agri-food analysis and quality control: THz can be a competitive detection method for inspecting hidden physiological threats and defects through its capability of recognizing foreign bodies, determining pesticide and antibiotic residues in agri-food products, and characterizing edible oils and genetically modified food.

5) Cultural heritage: non-destructive evaluation of the structures of targets or of hidden material and, therefore, suitability for non-invasive diagnostics for cultural heritage.

This Special Issue is an opportunity to further disseminate the scientific and technological development related to THz radiation.

Prof. Dr. Petrarca Massimo
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. Applied Sciences 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 2400 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.

• THz sources and detectors
• THz spectroscopy
• THz optics
• Linear and non-linear THz response of materials
• Dust and pollution
• Environmental science
• Metamaterials
• THz for communication
• THz for transmission line and waveguide
• THz applications
• THz propagation
• High-field THz
• THz for accelerator physics
• THz for plasma diagnostics
• Linear and non-linear optics