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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 17, Iss. 23 — Nov. 9, 2009
  • pp: 20675–20683

A terahertz plastic wire based evanescent field sensor for high sensitivity liquid detection

Borwen You, Tze-An Liu, Jin-Long Peng, Ci-Ling Pan, and Ja-Yu Lu  »View Author Affiliations

Optics Express, Vol. 17, Issue 23, pp. 20675-20683 (2009)

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A highly sensitive detection method based on the evanescent wave of a terahertz subwavelength plastic wire was demonstrated for liquid sensing. Terahertz power spreading outside the wire core makes the waveguide dispersion sensitive to the cladding index variation, resulting in a considerable deviation of waveguide dispersion. Two liquids with transparent appearances, water and alcohol, are easily distinguished based on the waveguide dispersion, which is consistent with theoretical predictions. A melamine alcohol solution with various concentrations is identified successfully, and the detection limit is up to 20ppm, i.e. equivalent to the index variation on the order of 0.01.

© 2009 OSA

OCIS Codes
(060.2370) Fiber optics and optical communications : Fiber optics sensors
(130.6010) Integrated optics : Sensors
(230.7370) Optical devices : Waveguides
(300.6495) Spectroscopy : Spectroscopy, teraherz

ToC Category:

Original Manuscript: September 24, 2009
Revised Manuscript: October 23, 2009
Manuscript Accepted: October 23, 2009
Published: October 27, 2009

Borwen You, Tze-An Liu, Jin-Long Peng, Ci-Ling Pan, and Ja-Yu Lu, "A terahertz plastic wire based evanescent field sensor for high sensitivity liquid detection," Opt. Express 17, 20675-20683 (2009)

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