High-resolution time-of-flight terahertz tomography using a femtosecond fiber laser

• Published in: Optics express Vol. 17; no. 9; pp. 7549 - 7555
• Main Authors: Takayanagi, Jun, Jinno, Hiroki, Ichino, Shingo, Suizu, Koji, Yamashita, Masatsugu, Ouchi, Toshihiko, Kasai, Shintaro, Ohtake, Hideyuki, Uchida, Hirohisa, Nishizawa, Norihiko, Kawase, Kodo
• Format: Journal Article
• Language: English
• Published: United States 27.04.2009
• Subjects: Computer-Aided Design; Equipment Design; Equipment Failure Analysis; Fiber Optic Technology - instrumentation; Lasers; Reproducibility of Results; Sensitivity and Specificity; Spectrum Analysis - instrumentation; Terahertz Radiation; Tomography, Optical - instrumentation
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/oe.17.007533

High-resolution tomographic imaging is demonstrated using a reflection-type terahertz time-domain spectroscopy. To realize a practical system for general use, a robust all-fiber laser was used as the pump light source. Broadband terahertz waves were generated with the combination of optical pulses compressed to 17 fs using optical fibers and a DAST crystal. Using deconvolution signal processing, the wideband spectrum of the generated terahertz waves provided high-axial resolution leading to successful imaging of a multilayered structure containing a 2-microm-thin GaAs layer. To our knowledge, this is the first demonstration of terahertz tomographic imaging of such a thin layer.