Chisel-edged screens to reduce loss in highly overmoded THz iris lines with finite screen thickness

Adham Naji; Karl Bane; Andrei Trebushinin; Paul Warr

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arXiv · 2409.01455

Chisel-edged screens to reduce loss in highly overmoded THz iris lines with finite screen thickness

Adham Naji·Karl Bane·Andrei Trebushinin·Paul Warr

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Abstract

In this note we report observations on the growth trends of diffraction power loss and ohmic power loss, as functions of screen thickness, in highly overmoded THz iris-line waveguides that are constructed from thin screens. Recent theoretical developments have given a detailed field description, including eigen and transient analyses, that characterizes such waveguides under paraxial dipole-mode excitation. Informed by these analyses, we can better estimate -- and minimize -- power loss effects due to finite screen thickness in practical realizations. A geometric variation is proposed whereby we limit the growth trend in ohmic loss, even when using relatively thicker screens in practice.

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Adham Naji, Karl Bane, Andrei Trebushinin, Paul Warr. 2024-09-02. Chisel-edged screens to reduce loss in highly overmoded THz iris lines with finite screen thickness. https://arxiv.org/abs/2409.01455

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