Proceedings Article | 16 February 2009
Proc. SPIE. 7277, Photonics and Optoelectronics Meetings (POEM) 2008: Terahertz Science and Technology
KEYWORDS: Refractive index, Beam splitters, Spectroscopy, Fourier transforms, Optoelectronics, Terahertz radiation, Antennas, Terahertz spectroscopy, Spectroscopes, Absorption
Many materials were previously studied using far-infrared Fourier transform spectroscopy (FTS) in transmission and
reflection modes. Recently, there has been a remarkable effort in employing terahertz time-domain spectroscopy (THz-TDS) for investigating material properties, including environment pollutants, semiconductors, polymers, explosive
materials, and gases, etc. Since the absorption coefficient and the refractive index of the material studied are directly
related to the amplitude and phase respectively of the transmitted field, both parts of the complex permittivity can be
obtained by THz-TDS. In this letter, the optical properties of peanut oils in the frequency range from 0.2 to 2.5 THz were
studied by employing terahertz time-domain spectroscopy. Several peanut oils, such as clean unused peanut oil, peanut
oil after five minutes of boiling, and peanut oil after ten minutes of boiling were tested. The time delays of clean unused
peanut oil, peanut oil after five minutes of boiling, and peanut oil after ten minutes of boiling are 8.33ps, 8.46ps and 8.46ps, respectively. The refractive indices of the three oil samples show slow a decrease as the terahertz wave frequency increases. The power absorption coefficients increase as the frequency increases within the investigated terahertz wave frequency range.
