Critical infrastructures are targets for terrorism and deliver a valuable vector through which the proliferation of CBRN and explosive precursors can be detected. Recent technological breakthroughs, notably in the field of near infrared (NIR), mid infrared (MIR), Terahertz (THz) and Gigahertz (GHz) sources and detectors, have led to rugged commercial devices, capable of standoff sensing a range of these dangerous substances. However, at the same time criminal and terrorist organizations have also benefited from the availability of technologies to increase the threat they pose to the security of citizens and a concerted effort is needed to improve early detection measures to identify activities, such as the production of homemade explosives or CBRN that can be potentially dangerous to society. The key global technological bottleneck to be overcome is the current lack of integration and networking of mature detection technology into early warning systems for critical infrastructures. Thus, this book brings together complementary information connecting the research of leading teams working on critical Infrastructure protection with academic developers and industrial producers of state of the art sensors.

Terahertz (THz) technology is an active area of research, but only in recent years has the application of THz waves (T waves) in food and agricultural industries been explored. Terahertz Technology: Principles and Applications in the Agri-Food Industry describes the operating principles of THz technology and discusses applications and advantages of the THz regime of the electromagnetic spectrum for use in the agri-food industry. The agri-food industry is focusing on the development of non-destructive quality evaluation techniques that can provide accurate analysis quickly and are environmentally friendly. Among such techniques is THz technology that provides a novel noninvasive approach to quality assessment and safety assurance of agri-food products. The low energy of T waves is best suited for the analysis of sensitive biomaterials and does not cause photoionization. Therefore, THz imaging is complementary to X-ray imaging. Although accessing the THz spectrum is tedious by conventional devices, the combination of optics and electronics principles has opened a dimension of research in this field. This book provides an overview of THz spectroscopy and imaging, system components, types of THz systems, and applications and advantages of THz for applications in the agri-food industry. It describes the basic working mechanism, operating principle, operation modes, and system components of THz spectroscopy and imaging. Various advancements in THz technology related to agricultural and food applications are discussed that could serve as a guidebook for all those working and interested in non-destructive food assessment techniques. Key Features: Explores broader applications of the THz regime in the agri-food sector Describes system components, different forms of THz systems, and the working principle of T waves for spectroscopic and imaging techniques Provides insights on future research needs for industrial implementation of THz technology Complements the knowledge of other existing non-destructive spectroscopy and imaging techniques for food analysis Although books on biomedical applications of THz have been published, no book is available that deals with applications in the agri-food industry. Hence, Terahertz Technology is beneficial for undergraduate and graduate students and those food industry professionals involved in research related to non-destructive quality assessment and imaging techniques.

Terahertz (THz) and Mid-Infrared (MIR) radiation (TERA-MIR) can be transmitted through nearly any material without causing biological harm. Novel and rapid methods of detection can be created with devices operation in these spectral ranges allowing scanning for weapons, detecting hidden explosives (including plastic landmines), controlling the quality of food and a host of other exciting applications. This book focuses on mathematical and physical aspects of the field, on unifying these two spectral domains (THz and MIR) with regard to common sources, detectors, materials and applications, and on key interdisciplinary topics. The main THz and MIR source is the quantum cascade laser (QCL). Thus significant attention is paid to the challenge of turning this advanced technology into affordable commercial devices so as to exploit its enormous potential. However other alternatives to THz QCLs are also presented, e.g. sub-terahertz imaging from avalanching GaAs bipolar transistors, Josephson junctions as THz sources, semiconductor materials for pulsed THz sources, superconducting THz electronics with Josephson vortices. In summary this book delivers a global picture of the state of the art in TERA-MIR generation, detection and applications.

This work is intended to jointly address the development, realization and applications of emitters and detectors of terahertz (THz-0.3 THz up to 10 THz) and their application to diagnostics of CBRN effects and detection of explosives and CBRN. Hazardous substances typically exhibit rotational and vibrational transitions in this region, hence giving access to spectroscopic analysis of a large variety of molecules which play a key role in security as well as various other areas, e.g. air pollution, climate research, industrial process control, agriculture, food industry, workplace safety and medical diagnostics can be monitored by sensing and identifying them via THz (0.3 to 10 THz) and mid infrared (MIR-10 THz to 100 THz) absorption “finger prints”. Most plastics, textiles and paper are nearly transparent for THz radiation.

The inherent advantages and potential payoffs of the terahertz (THz) regime for military and security applications serve as an important driver for interest in new THz-related science and technology. In particular, the very rapid growth in more recent years is arguably most closely linked to the potential payoffs of THz sensing and imaging (THz-S&I).This book presents some of the leading fundamental research efforts towards the realization of practical THz-S&I capabilities for military and security applications. Relevant subjects include theoretical prediction and/or measurement of THz spectroscopic phenomenon in solid-state materials such as high explosives (e.g. HMX, PETN, RDX, TNT, etc.), carbon-fiber composites, biological agents (e.g. DNA, RNA, proteins, amino acids) and organic-semiconductor nanostructures. Individual papers also address the effective utilization of state-of-the-art THz-frequency technology in military and security relevant scenarios such as standoff S&I, screening of packages and personnel, and perimeter defense. Technical papers introduce novel devices and/or concepts that enhance THz source and detector performance, enabling completely new types of sensor functionality at THz frequency (e.g. detection at nanoscale/molecular levels), and defining new and innovative sensing modalities (e.g. remote personnel identification) for defense and security. Therefore, the collective research presented here represents a valuable source of information on the evolving field of THz-S&I for military and security applications.

These proceedings comprise invited papers from highly experienced researchers in THz technology and security applications. THz detection of explosives represents one of the most appealing technologies to have recently emerged in dealing with terrorist attacks encountered by civil security and military forces throughout the world. Discussed are the most advanced technologies and developments, the various points of operational strength and weaknesses as well as are suggestions and predictions the best technological solutions to overcome current operational limits. The current status of various levels of cooling in THz detectors, sources and associated electronics are also addressed. The goal was to provide a clear view on the current technologies available and the required advances needed in order to achieve more efficient systems. This goal was outlined in part by establishing the baseline of current uncertainty estimations in physics-based modelling and the identification of key areas which require additional research and development.

The last research frontier in high frequency electronics now lies in the so-called THz (or submillimeter-wave) regime between the traditional microwave and infrared domains. Significant scientific and technical challenges within the terahertz (THz) frequency regime have recently motivated an array of new research activities. During the last few years, major research programs have emerged that are focused on advancing the state of the art in THz frequency electronic technology and on investigating novel applications of THz frequency sensing. This book serves as a detailed reference for the new THz frequency technological advances that are emerging across a wide spectrum of sensing and technology areas.

Infrared, Millimeter Wave and Terahertz Science, Technology and Applications

This book highlights recent advances and applications in terahertz (THz) technology, addressing advanced topics such as THz biomedical imaging, pattern recognition and tomographic reconstruction for THz biomedical imaging by machine learning and artificial intelligence, THz imaging radars for autonomous vehicle applications, and THz imaging systems for security and surveillance. It also discusses theoretical, experimental, established and validated empirical work on these topics.