Terahertz and Mid Infrared Radiation: Detection of Explosives and CBRN (Using Terahertz), 2014
NATO Science for Peace and Security Series B: Physics and Biophysics Series

The reader will find here a timely update on new THz sources and detection schemes as well as concrete applications to the detection of Explosives and CBRN. Included is a method to identify hidden RDX-based explosives (pure and plastic ones) in the frequency domain study by Fourier Transformation, which has been complemented by the demonstration of improvement of the quality of the images captured commercially available THz passive cameras. The presented examples show large potential for the detection of small hidden objects at long distances (6-10 m). Complementing the results in the short-wavelength range, laser spectroscopy with a mid-infrared, room temperature, continuous wave, DFB laser diode and high performance DFB QCL have been demonstrated to offer excellent enabling sensor technologies for environmental monitoring, medical diagnostics, industrial and security applications. From the new source point of view a number of systems have been presented - From superconductors to semiconductors, e.g. Detection of Terahertz Waves from Superconducting Bi₂Sr₂CaCu₂O₈+? Intrinsic Josephson Junctions. The quest for a compact room temperature THz source and the recent advances in high power mid-IR QCLs lead to the development of a semiconductor THz source based on intracavity difference frequency generation. Furthermore, alternative electrically pumped THz sources based on the high emission efficiency predicted for polaritonic states in the ultra-strong coupling regime led to the demonstration of electroluminescent devices. Finally, antipolaritons in dispersive media were discussed and different aspects of the interaction of THz radiation with biomatter were presented.

THz Hybrid Metamaterial-Liquid Crystal Based Structures with Large Tunability.- High-Resolution THz Spectroscopy of Biomolecules and Bioparticles: Concentration Methods.- Intervalence THz Antipolaritons.- Terahertz Aperiodic Multilayered Structure Arranged According to the Kolakoski Sequence.- Population Dynamic in Quantum Cascade GaN/AlGaN Photodetector Structure.- Design of Metamaterial Photonic Crystals for Explosives Detection.- New Type High-Q THz Planar All-Dielectric Metamaterial.- Bipolar THz-lasing Structures Based on InAs-GaSb Coupled Quantum Wells and their Potential for Security Checks.- Coherent Quantum Control of Donor States in Silicon with THz and MIR Light: a Route Towards a Scalable Quantum Computing Architecture.- THz Bio-Chemical Sensing Capabilities with High Performance SIW Based Sensor on nL-volume Liquids in Capillary.- A Theoretical Study on Monitoring Explosives Degradation by Pentaerythritol Tetranitrate Reductase Using THz Spectroscopy.- Area Dependence of Josephson Critical Current Density in Superconducting Bi₂Sr₂CaCu₂O_8+d  for Terahertz Emission.- Inhomogenity of Micron-Sized Triple Terahertz Emitters Fabricated from Intrinsic Josephson Junctions in Single Crystal Bi₂Sr₂CaCu₂O_8+δ .- The Fourier Transformed MIR Microspectroscopy to Reveal a Morphological and Spectral Markers of a Cervical Cancer Cells.- THz Diffractive Optical Element for Passive Imaging.- Intersubband Dispersive Gain Media.- Recent Advances in IR Laser Diodes with High Power, high WPE, Single Mode, CW Operation at RT.- Determination of the Index of Refraction and Absorption Coefficient by THz-TDS of TlInS₂, TlGaTe₂  and InSe Crystals.- Ultrashort Electromagnetic Modes in the Low Frequency Region of the Spectrum in a Nanocylinder Array.- Influence of Mesa-Fabrication-Dependent Waveguide-Sidewall Roughness on Threshold Current and Slope Efficiency of AlGaAs/GaAs Mid-Infrared Quantum-Cascade Lasers.- Mid-Infrared Laser Based Gas Sensor Technologies for Environmental  Monitoring, Medical Diagnostics, Industrial and Security Applications.- Computer Processing of Images Captured with a Commercially Available THz Camera at Long Distances.- Transmission Subterahertz Imaging Utilizing Milliwatt-Range Nanosecond Pulses from Miniature, Collapsing-Domain-Based Avalanche Source.- Sub-THz Spectroscopy for Security Related Gas Detection.

Recent update on new methods for generating THz and Mid Infrared Radiation at room temperature

New efficient detection schemes for explosive, CBRN and small object detection

Advances in the study of the coupling of THz radiation with matter and notably biomatter

Includes supplementary material: sn.pub/extras