We present an experimental terahertz (THz) spectroscopic investigation of amino acid using an air-breakdown-coherent detection (ABCD) system. The strong and ultra-broadband (0.1 to 10THz) terahertz radiations generated by two-color laser induced air plasma and measured by coherent heterodyne detection. The broadband THz reflection spectra of L-Lysine (C₆H₁₄N₂O₂) and L-Arginine (C₆H₁₄N₂O₂) are obtained. To solve the phase-retrieval problem in RTDS, the absorption signatures of the materials are extracted directly from the first derivative of the relative reflectance with respect to frequency. The absorption features of the two amino acids are characterized in the 0.5~6 THz region. It is found that both the two amino acids have an absorption peak at 1.10 THz.

Date Published: 11 August 2011
PDF: 6 pages
Proc. SPIE 8195, International Symposium on Photoelectronic Detection and Imaging 2011: Terahertz Wave Technologies and Applications, 819514 (11 August 2011); doi: 10.1117/12.900765

Published in SPIE Proceedings Vol. 8195:
International Symposium on Photoelectronic Detection and Imaging 2011: Terahertz Wave Technologies and Applications
X.-C. Zhang; Jianquan Yao; Cunlin Zhang; Zhenzhan Wang, Editor(s)