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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 20, Iss. 17 — Aug. 13, 2012
  • pp: 19176–19184

Characterization of bending loss in hollow flexible terahertz waveguides

Pallavi Doradla, Cecil S. Joseph, Jayant Kumar, and Robert H. Giles  »View Author Affiliations

Optics Express, Vol. 20, Issue 17, pp. 19176-19184 (2012)

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Attenuation characteristics of hollow, flexible, metal and metal/dielectric coated polycarbonate waveguides were investigated using an optically pumped far infrared (FIR) laser at 215 µm. The bending loss of silver coated polycarbonate waveguides were measured as a function of various bending angles, bending radii, and bore diameters. Minimal propagation losses of 1.77, 0.96 dB/m were achieved by coupling the lowest loss TE11 mode into the silver or gold coated waveguide, and HE11 mode into the silver/polystyrene coated waveguides respectively. The maximal bending loss was found to be less than 1 dB/m for waveguides of 2 to 4.1 mm bore diameters, with a 6.4 cm bend radius, and up to 150° bending angle. The investigation shows the preservation of single laser mode in smaller bore waveguides even at greater bending angles.

© 2012 OSA

OCIS Codes
(230.7370) Optical devices : Waveguides
(040.2235) Detectors : Far infrared or terahertz
(110.6795) Imaging systems : Terahertz imaging

ToC Category:
Optical Devices

Original Manuscript: June 4, 2012
Revised Manuscript: July 16, 2012
Manuscript Accepted: July 31, 2012
Published: August 6, 2012

Pallavi Doradla, Cecil S. Joseph, Jayant Kumar, and Robert H. Giles, "Characterization of bending loss in hollow flexible terahertz waveguides," Opt. Express 20, 19176-19184 (2012)

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