THz gas sensing with submillimeter techniques (Invited Paper)

There has been considerable interest in the use of the Submillimeter/THz (SMM/THz) spectral region for gas analysis and detection. This has been driven both by the importance of the application and the THz-TDS community. In this paper we will discuss and compare the attributes of an attractive alternative: cw submillimeter spectroscopy. Particular attention will be paid to sensitivity, specificity, and the investigations of harsh environments. A particularly simple system approach, the FAst Scan Submillimeter Spectroscopy Technique (FASSST), will be discussed and a compact and potentially very low cost implementation described. Results will be presented which include the analyses of complex mixtures of gases with absolute specificity.