On-chip terahertz fingerprint sensing of pesticide

Terahertz spectroscopy contains rich and unique fingerprint spectral information about substances and has received continuous attention in the fields of physics, chemistry, and biology. Among these, the detection of terahertz fingerprints of trace substances is an important topic for understanding the natural laws of microscopic systems. To achieve highly sensitive detection of terahertz fingerprint spectra of trace substances in a broad spectrum, a terahertz spectral sensing chip based on broadband antenna coupling and deep subwavelength slotline waveguide enhancement is proposed and validated in this paper. The on-chip detection of 1.0 mg of pesticide powder was successfully obtained near 0.87 THz, and the results were consistent with the free-space fingerprint of pesticide powder. This work provides an efficient means of detection for the study of microscopic systems using terahertz waves.