Security screening system based on terahertz-wave spectroscopic gas detection

• DOI: 10.1364/oe.413201
• Publication Date: 2020-12-28T02:30:09Z
• Authors: Yuma Takida; Kouji Nawata; Hiroaki Minamide
• Keywords: Trace gas

Tunable terahertz (THz)-wave absorption spectroscopy is a promising technique to detect trace gases suspended in ambient air owing their strong fingerprints the THz-wave spectral region. Here, we present spectroscopic gas detection platform based on frequency-tunable injection-seeded parametric generator and compact multipass cells. Using 1.8-m-path-length cell, detected gas-phase methanol (CH 3 OH) down concentration of 0.2 ppm at 1.48-THz transparent atmospheric window. We also developed transportable walk-through screening prototype using 6-m-path-length cell identify suspicious subjects. Our results demonstrate potential proposed system for security applications.