Bao, Hualong1; Nielsen, Kristian1; Rasmussen, Henrik K.3; Jepsen, Peter Uhd6; Bang, Ole1
1 Department of Photonics Engineering, Technical University of Denmark2 Fiber Sensors and Supercontinuum Generation, Department of Photonics Engineering, Technical University of Denmark3 Department of Mechanical Engineering, Technical University of Denmark4 Manufacturing Engineering, Department of Mechanical Engineering, Technical University of Denmark5 Teraherts Technologies and Biophotonics, Department of Photonics Engineering, Technical University of Denmark6 Center for Nanostructured Graphene, Center, Technical University of Denmark
We present a numerical and experimental investigation of a low-loss porous-core honeycomb fiber for terahertz wave guiding. The introduction of a porous core with hole size of the same dimension as the holes in the surrounding honeycomb cladding results in a fiber that can be drawn with much higher precision and reproducibility than a corresponding air-core fiber. The high-precision hole structure provides very clear bandgap guidance and the location of the two measured bandgaps agree well with simulations based on finite-element modeling. Fiber loss measurements reveal the frequency-dependent coupling loss and propagation loss, and we find that the fiber propagation loss is much lower than the bulk material loss within the first band gap between 0.75 and 1.05 THz.
Optics Express, 2012, Vol 20, Issue 28, p. 29507-29517