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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 18, Iss. 6 — Mar. 15, 2010
  • pp: 6097–6107

Molecular properties of liquid crystals in the terahertz frequency range

Nico Vieweg, Christian Jansen, Mohammad Khaled Shakfa, Maik Scheller, Norman Krumbholz, Rafal Wilk, Martin Mikulics, and Martin Koch  »View Author Affiliations


Optics Express, Vol. 18, Issue 6, pp. 6097-6107 (2010)
http://dx.doi.org/10.1364/OE.18.006097


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Abstract

We report on a first experimental study of the molecular properties of nematic liquid crystals in the terahertz range. In the beginning, we extract the frequency and temperature dependent refractive index and absorption coefficient of the cyanobiphenyls 5CB, 6CB and 7CB from terahertz time domain spectroscopy measurements and investigate the impact of the alkyl chain length on the macroscopic liquid crystal characteristics, focusing especially on the pronounced odd and even effect. Next, we deduce the principle polarizabilities and the order parameter S by applying Vuks’ approximation and Haller’s approach. On this basis, we calculate the main polarizabilities along the longitudinal and transverse axis and link the observed terahertz properties to the molecular structure of the liquid crystals.

© 2010 Optical Society of America

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

ToC Category:
Materials

History
Original Manuscript: January 5, 2010
Revised Manuscript: March 9, 2010
Manuscript Accepted: March 9, 2010
Published: March 11, 2010

Citation
Nico Vieweg, Christian Jansen, Mohammad Khaled Shakfa, Maik Scheller, Norman Krumbholz, Rafal Wilk, Martin Mikulics, and Martin Koch, "Molecular properties of liquid crystals in the terahertz frequency range," Opt. Express 18, 6097-6107 (2010)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-18-6-6097


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