Thin chalcogenide capillaries as efficient waveguides from mid-infrared to terahertz

Abstract

We present chalcogenide glass As 2 Se 3 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 µm and up to 130 µm. 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.

Two-wire terahertz fibers with porous dielectric support

“…This thickness is defined as the smallest distance between the fiber outer surface and the boundary of the internal air holes. From our experience with plastic porous fibers and capillaries [11,21], outer cladding thickness larger than 50 µm is sufficient to mechanically protect the inner structure of the fiber. In our calculations, the smallest bridge size between any two air holes is taken to be 10 µm, which can be readily realised in practice as demonstrated in our prior experiments with suspended core fibers [3].…”

“…The main challenge in the design of such fibers is to ensure high reflection at the core-cladding interface. Different hollow-core structures have been investigated including metalized bores [5][6][7], periodic dielectric multilayers [8], as well as thin-walled dielectric pipes [9][10][11]. Among other types of the THz waveguides, we note parallel plate waveguides [12] and slit waveguides [13], which are known for their low losses and strong confinement.…”

Mid-IR supercontinuum generation in dispersion flattened As38Se62 chalcogenide photonic crystal fiber

“…As 38 Se 62 have certain advantages and features by which we and many researchers are attracted by this material, it have huge stability against crystallization process than As 2 Se 3 . Apart from these features, additional features are low-loss nature and high transition temperature (165 0 C) which makes its appropriate for SC generation in Mid-IR region [11][12]. Works done by keeping As 38 Se 62 as fiber material have several evidences.…”

Hybrid metal wire–dielectric terahertz waveguides: challenges and opportunities [Invited]

“…The main challenge in the design of such fibers is to ensure high reflection at the core-cladding interface. Different hollow-core structures have been investigated including metalized bores [5][6][7], periodic dielectric multilayers [8], as well as thin-walled dielectric pipes [9][10][11] and tube lattice fibers [12]. These fibers, however, have a tendency of having a large core size that can easily be 10 times larger than the wavelength of guided light.…”