Thin chalcogenide capillaries as efficient waveguides in the mid-IR -   THz spectral range
  We present chalcogenide glass As2Se3 capillaries as efficient waveguides in the mid-IR and THz spectral ranges. The capillaries are fabricated using a double crucible glass drawing technique. The wall thickness of the glass capillary is properly designed and controlled during drawing, and we are able to produce capillaries with different wall thickness, starting from 12 \mum and up to 130 \mum. Such capillaries show low loss properties in the whole target wavelength region. In the mid-IR range guidance is governed by Fresnel reflection and antiguidance mechanisms (ARROWs), while in the THz spectral range thin walls capillaries guide via total internal reflection. 
Anna Mazhorova, Andrey Markov, Bora Ung, Mathieu Roz\'e, Stepan   Gorgutsa, and Maksim Skorobogatiy
physics.optics