Document Type : Research
Authors
1 Department of Physics Education, Farhangian University, P.O. Box 14665-889, Tehran, Iran.
2 Ph.D. Student, Department of Physics, Azarbaijan Shahid Madani University, Tabriz, Iran.
Abstract
Waveguides are optical structures designed to guide electromagnetic waves, whose performance and losses are strongly influenced by design parameters such as dimensions, geometry, bending, and constituent materials. In this article, wave propagation in rectangular waveguides with a 90-degree bend and U-shaped waveguides is studied in the presence of cold electron plasma. To this end, specific sections, including the bend regions and the input or output ports, are considered to be filled with cold electron plasma, while the remaining parts are assumed to be empty (air). Simulations were performed using the Finite Element Method (FEM) in the COMSOL software suite within the frequency range of 4.25 to 7 GHz. The Scattering parameters (S-parameters), including reflected and transmitted coefficients, were extracted and analyzed. The results reveal the emergence of multiple resonant modes in the reflection spectrum when plasma is utilized in the bend regions. Furthermore, the effects of varying the plasma density and the intensity of an applied magnetostatic field on the magnetized plasma have been investigated with respect to the resonance frequencies. The findings clearly confirm the capability to control the resonance frequencies and the losses induced by bending through the adjustment of these external parameters. This controllability renders the aforementioned waveguides highly promising candidates for various practical and research-oriented applications.
Keywords
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