Flexible, Low-loss Waveguide Designs for Efficient Coupling to Quantum Cascade Lasers in the Far-infrared

  • Ugo Siciliani de Cumis
  • Ji-Hua Xu
  • Carlos M. Bledt
  • James A. Harrington
  • Alessandro Tredicucci
  • Miriam S. Vitiello


We coupled linearly polarized and azimuthally polarized Terahertz quantum cascade lasers (QCLs) to the low-loss optical modes of hollow core waveguides having a sequence of different metallic or dielectric inner coatings. The latter waveguides have been specifically designed to force the propagation of a dominant optical mode once the thickness (d) of the inner dielectric coating is properly chosen. Our results demonstrate that both the TE01 and the TE11 modes can be easily converted to a hybrid one when d > 6 μm allowing the propagation of THz QCL beams with transmission losses as low as 1.5 dB/m, bending losses < 1.1 dB and reasonably high coupling efficiencies (87%).


Waveguides Quantum cascade lasers Terahertz 



The authors would like to greatly acknowledge Oleg Mitrofanov for useful discussions


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Ugo Siciliani de Cumis
    • 1
  • Ji-Hua Xu
    • 1
  • Carlos M. Bledt
    • 2
  • James A. Harrington
    • 2
  • Alessandro Tredicucci
    • 1
  • Miriam S. Vitiello
    • 1
  1. 1.NEST, CNR—Istituto Nanoscienze and Scuola Normale SuperiorePisaItaly
  2. 2.Department of Materials Science and EngineeringRutgers UniversityPiscatawayUSA

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