Final published version
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Investigation of hollow cylindrical metal terahertz waveguides suitable for cryogenic environments
AU - Wallis, R.
AU - Degl'Innocenti, Riccardo
AU - Jessop, D. S.
AU - Mitrofanov, O.
AU - Bledt, C. M.
AU - Melzer, J. E.
AU - Harrington, J. A.
AU - Beere, H. E.
AU - Ritchie, D. A.
PY - 2016/12/26
Y1 - 2016/12/26
N2 - The field of terahertz (THz) waveguides continues to grow rapidly, with many being tailored to suit the specific demands of a particular final application. Here, we explore waveguides capable of enabling efficient and accurate power delivery within cryogenic environments (<4 K). The performance of extruded hollow cylindrical metal waveguides made of un-annealed and annealed copper, as well as stainless steel, have been investigated for bore diameters between 1.75 - 4.6 mm, and at frequencies of 2.0, 2.85 and 3.4 THz, provided by a suitable selection of THz quantum cascade lasers. The annealed copper resulted in the lowest transmission losses, <3 dB/m for a 4.6 mm diameter waveguide, along with 90° bending losses as low as ∼2 dB for a bend radius of 15.9 mm. The observed trends in losses were subsequently analyzed and related to measured inner surface roughness parameters. These results provide a foundation for the development of a wide array of demanding lowtemperature THz applications, and enabling the study of fundamental physics.
AB - The field of terahertz (THz) waveguides continues to grow rapidly, with many being tailored to suit the specific demands of a particular final application. Here, we explore waveguides capable of enabling efficient and accurate power delivery within cryogenic environments (<4 K). The performance of extruded hollow cylindrical metal waveguides made of un-annealed and annealed copper, as well as stainless steel, have been investigated for bore diameters between 1.75 - 4.6 mm, and at frequencies of 2.0, 2.85 and 3.4 THz, provided by a suitable selection of THz quantum cascade lasers. The annealed copper resulted in the lowest transmission losses, <3 dB/m for a 4.6 mm diameter waveguide, along with 90° bending losses as low as ∼2 dB for a bend radius of 15.9 mm. The observed trends in losses were subsequently analyzed and related to measured inner surface roughness parameters. These results provide a foundation for the development of a wide array of demanding lowtemperature THz applications, and enabling the study of fundamental physics.
U2 - 10.1364/OE.24.030002
DO - 10.1364/OE.24.030002
M3 - Journal article
AN - SCOPUS:85009284654
VL - 24
SP - 30002
EP - 30014
JO - Optics Express
JF - Optics Express
SN - 1094-4087
IS - 26
ER -