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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 20, Iss. 27 — Dec. 17, 2012
  • pp: 28249–28256

Ultrabroadband terahertz spectroscopy of a liquid crystal

N. Vieweg, B. M. Fischer, M. Reuter, P. Kula, R. Dabrowski, M. A. Celik, G. Frenking, M. Koch, and P. U. Jepsen  »View Author Affiliations

Optics Express, Vol. 20, Issue 27, pp. 28249-28256 (2012)

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Liquid crystals (LCs) are becoming increasingly important for applications in the terahertz frequency range. A detailed understanding of the spectroscopic parameters of these materials over a broad frequency range is crucial in order to design customized LC mixtures for improved performance. We present the frequency dependent index of refraction and the absorption coefficients of the nematic liquid crystal 5CB over a frequency range from 0.3 THz to 15 THz using a dispersion-free THz time-domain spectrometer system based on two-color plasma generation and air biased coherent detection (ABCD). We show that the spectra are dominated by multiple strong spectral features mainly at frequencies above 4 THz, originating from intramolecular vibrational modes of the weakly LC molecules.

© 2012 OSA

OCIS Codes
(160.3710) Materials : Liquid crystals
(300.6495) Spectroscopy : Spectroscopy, teraherz

ToC Category:

Original Manuscript: October 3, 2012
Revised Manuscript: November 23, 2012
Manuscript Accepted: November 24, 2012
Published: December 5, 2012

N. Vieweg, B. M. Fischer, M. Reuter, P. Kula, R. Dabrowski, M. A. Celik, G. Frenking, M. Koch, and P. U. Jepsen, "Ultrabroadband terahertz spectroscopy of a liquid crystal," Opt. Express 20, 28249-28256 (2012)

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