Terahertz (THz), Mid Infrared (MIR) and Near Infrared (NIR) Technologies for Protection of Critical Infrastructures Against Explosives and CBRN

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. Preface Why GHz-THz-MIR? Acknowledgements Contents Part I: State of the Art in Sensors for the Protection of Critical Infrastructures Chapter 1: Sensor Data Fusion and Autonomous Unmanned Vehicles for the Protection of Critical Infrastructures 1.1 Introduction 1.2 Multi-sensor Image Fusion 1.2.1 Image Decomposition 1.2.2 Fusion Scheme 1.3 Object Identification for Surveillance Objectives 1.4 Experimental Results 1.5 Conclusions References Part II: Beyond QCLs, ICLs and Superlattices: Competing Technologies for Detection of Explosives and CBRN Chapter 2: High Power, Widely Tunable, and Beam Steerable Mid-infrared Quantum Cascade Lasers 2.1 Introduction 2.2 Monolithic Tunable QCL Array Based on a Heterogeneous Broadband Wafer 2.3 High Performance Broadband Monolithic Tunable QCLs 2.4 High Power Phase-Locked QCL Arrays 2.5 Single-Mode, High-Power, Phase-Locked QCL Arrays 2.6 Summary References Chapter 3: Broadband Terahertz Gas Spectroscopy Through Multimode Self-Mixing in a Quantum Cascade Laser 3.1 Introduction 3.2 Device Process 3.3 Experimental Setup 3.4 Self-Mixing Gas Spectroscopy 3.5 Conclusions References Chapter 4: Crucial Aspects of the Device Processing of Quantum Cascade Lasers 4.1 Introduction 4.2 Crucial Aspects of THz QCLs Processing 4.3 Conclusion References Chapter 5: Broadband Gas QEPAS Detection Exploiting a Monolithic DFB-QCL Array 5.1 Introduction 5.2 Experimental Setup 5.3 Laser Source Characterization and Sensor Configuration 5.4 Broadband Absorbers Detection and Sensor Performance 5.4.1 Nitrous Oxide Detection and Spectrum Reconstruction 5.4.2 Methane Detection and Spectrum Reconstruction 5.5 Conclusion References Chapter 6: Global Optimization Methods for the Design of MIR-THz QCLs Applied to Explosives Detection 6.1 Introduction 6.2 Global Optimization Methods Used on QCLs 6.2.1 Simulated Annealing Algorithm 6.2.2 Genetic Algorithm 6.2.3 Variational Calculus 6.3 Isospectral Transformations of the Hamiltonian 6.3.1 Supersymmetric Transform 6.3.2 Coordinate Transform 6.4 Conclusions References Part III: Superlattices and Other Technologies for GHz-THz Sensing Chapter 7: Non-destructive Testing THz Systems: Fast Postal Scanner Case Study 7.1 Introduction 7.2 Non-destructive Material Testing 7.3 Terahertz Radiation 7.4 Postal Fast-Scanning System in the THz Range 7.5 Summary and Further Developments References Chapter 8: Recent Advances in Superlattice Frequency Multipliers 8.1 Introduction 8.2 Mathematical Formalism 8.2.1 Balance Equations and Effect Of Interface Roughness Scattering 8.3 Even-Harmonic Generation due to Designed Structural Variations of SSLs. 8.4 Photon-Assisted Transport and Harmonic Emission 8.5 Conclusion References Chapter 9: Solid-State Millimeter-Wave Through Terahertz Transceivers 9.1 Introduction 9.2 Diode Frequency Multiplier Based Sources 9.2.1 Varistor Multiplier Sources 9.2.2 Varactor Multiplier Sources 9.2.3 Compact Tunable Multiplier Based Millimeter-Wave Sources 9.3 Diode Mixer and Detector Based Receivers References Chapter 10: Transmission and Reflection Characteristics of Textiles in the Terahertz Range 10.1 Introduction 10.2 Time Domain Spectroscopy 10.3 Measurement Setup 10.4 Samples 10.5 Transmission Configuration - Setup, Methodology and Results 10.6 Reflection Configuration - Setup, Methodology and Results 10.7 Summary References Chapter 11: Transition Between Localized and Delocalized Terahertz Conductivity in Modulated Nanostructures Studied by Monte-C... References Chapter 12: THz Sources and Detectors Fabricated from High Temperature Superconductors 12.1 Introduction 12.2 Terahertz Sources 12.3 Terahertz Detectors 12.4 THz Filters 12.5 Conclusion References Chapter 13: Semiconductor Components for THz-TDS Systems Activated by Compact Fibre Lasers 13.1 Introduction 13.2 Mechanism of Surface THz Emission from Semiconductors 13.3 Experimental Technique 13.4 THz Excitation Spectra of Semiconductors 13.5 Optoelectronic THz Frequency Range Components from Dilute Bismides 13.6 Conclusions References Chapter 14: Soft Chemical Ionization Mass Spectrometric Analyses of Hazardous Gases and Decomposition Products of Explosives i... 14.1 Introduction 14.2 Quantitative Mass Spectrometry Techniques for Trace Gas Analysis 14.2.1 Selected Ion Flow Tube Mass Spectrometry (SIFT-MS) 14.2.2 Proton Transfer Reactions Mass Spectrometry (PTR-MS) 14.2.3 Selected Ion Flow Drift-Tube Mass Spectrometry (SIFDT-MS) 14.3 Decomposition Products of Explosives 14.4 Conclusions References Chapter 15: On the Prospect of Application of Point-Contact Sensors to Solving the Global Security Problems: An Analytical Rev... 15.1 Introduction 15.2 Detection of Marker Components 15.3 Spectral-Type Sensor Analysis 15.3.1 Detection of the Virulent Strains of Helicobacter pylori Infection 15.3.2 Sensor Profiling of Breath Gas as a Tool to Thwart Terror Attacks 15.3.3 Selective Quantum Sensors for Impact Monitoring of Environment and Defence Against CBRNE Agents 15.4 Conclusions References Chapter 16: Development of Gas Sensor Systems in the Infrared Region 16.1 Introduction 16.2 Study and Characterization of Microstructured Optical Fibers 16.2.1 Microstructure Sizing by Microscopy and Near Field Measurement 16.2.2 Light Coupling Test with Gas C2H2 and CO2 16.3 Scanning System Based on Laser Ring 16.4 Conclusions References Chapter 17: Raman Cooperative UV Generation with Possible Applications in Microbiology 17.1 Introduction 17.2 Description of the Theory in the Raman Process 17.3 Quantum Solution of Master Equation 17.4 Conclusions References Chapter 18: THz Spectroscopy of Advanced Materials 18.1 Introduction 18.1.1 ZnO Nanopowders 18.1.2 Graphene-Like Layers in Eumelanin 18.1.3 Transition Metal Dichalcogenides 18.2 Sample Preparation and Structural Characterization 18.2.1 ZnO Nanopowders 18.2.2 GL and EUGL Pellets 18.2.2.1 WSe2 and MoSe2 Films 18.3 Experimental 18.4 Theoretical Background 18.5 THz Spectroscopy 18.5.1 ZnO 18.5.2 GL and EUGL 18.5.3 TMD 18.6 Conclusions References Chapter 19: Development of Stand-Off Imaging Systems Using Low Cost Plasma Detectors That Work in the GHz to THz Range 19.1 Introduction 19.2 Detection Mechanism 19.2.1 Parallel 1d3v PIC/MCC Simulation of GDD 19.3 Low and High Frequency Response of the GDD 19.4 Conclusion References