Terahertz frequency sensing has a unique part to play in the detection and identification of materials and objects. This frequency range, corresponding to a wavelength of around 0.1 mm, can be used to identify materials from their molecular spectra and to produce images of concealed objects. Terahertz spectra of drugs of abuse and explosives presented by a number of the contributing authors show that the presence of these materials can be detected in envelopes, packages and through clothing.
The technology of terahertz detection has largely been developed around expensive and bulky femtosecond laser systems but, as described in this book, advances in semiconductor superlattice technology are leading to compact “electronic” sources such as the quantum cascade laser, two-terminal “Gunn” type oscillators and even a THz frequency amplifier. These advances towards electronic (as opposed to optical) THz systems mean that the technology will become portable and much less costly.
Terahertz remote sensing is also discussed with the possibility of detection over distances of up to 30m using existing technology or even through the use THz waves generated locally in the vicinity of a target using only air as the transducer.
Organizing Committee.- Sponsors.- Preface.- Theme 1: Terahertz Devices.- Terahertz Emission from Semiconductors Excited by Ultrafast Laser Pulses; A. Krotkus et al.-Terahertz Generation by Multiplication; J. Stake et al.- Towards Superlattice THz Amplifiers and Lasers; A. Lisauskas et al.- Tailoring the Emission of Terahertz Quantum Cascade Lasers; R. Green et al.- Guided Propagation of Terahertz Pulses on Metal Wires; K. Wang and D.M. Mittleman.- Superlattice and Other Negative-Differential Resistance Devices: Current Status; H. Eisele.-Theme 2: Interactions.- Molecular and Organic Interactions; A.G. Davies and E.H. Linfield .- Terahertz Beam Interactions with Amorphous Materials; M. Naftaly and R.E. Miles.- Development of Tagless Biosensors for Detecting the Presence of Pathogens; Jing–Yin Chen et al.- Theme 3: Detection and Sensing.-Improvements to Electronic Techniques for THz Spectroscopic Detection; D.W. van der Weide et al.-Terahertz Time-Domain Spectroscopy of Crystalline and Aqueous systems; P.U. Jepson et al.- Continuous-Wave Terahertz Photomixer Systems For Real World Applications; I.S. Gregory et al.- Theme 4: Systems for Security.- Systems Requirements for A Multi-Channel THz Contraband Scanner; W.S. Truscott.- Challenges to THz Counter Terrorism & Security Related Applications; H. Cummins.- Terahertz Detection of Illegal Objects; R. Appleby et al.- THz Rays to Detect Drugs of Abuse; K. Kawase et al.-Terahertz Spectroscopy for Explosive, Pharmaceutical and Biological Sensing Applications; Hai-Bo Liu and Xi-Cheng Zhang.- Terahertz Communications: a 2020 vision; M. Koch.- Theme 5.- Applied Terahertz Science: The Technology of the Future, and Always Will Be?; M. Chamberlain.- List of Speakers.- List of participants.- Group Photograph.- Index.-
