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arXiv · 2501.12042

Wakefield-induced THz wave generation in a hybrid dielectric-plasma cylindrical waveguide

A. A. Molavi Choobini·F. M. Aghamir
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Abstract

In the present study, the generation of THz radiation through wakefield excitation in a cylindrical dielectric plasma waveguide is investigated. The proposed hybrid dielectric-plasma wakefield structure combines the advantages of dielectric materials and plasma, creating a versatile platform for high-performance applications and advanced THz radiation generation. By leveraging the strengths of both techniques, this hybrid configuration achieves enhanced gradients and optimized THz wave output. The mechanism involves a high-energy laser pulse propagating through a plasma-loaded dielectric waveguide, inducing wakefields that drive THz wave emission. This dual capability underscores the versatility of the proposed structure, offering significant advancements in THz wave generation technologies. To support the theoretical analysis, numerical simulations were employed using the Fourier-Bessel Particle-In-Cell (FBPIC) method and the COMSOL Multiphysics package. The simulation modeled the wakefield generation process and validated the propagation of electromagnetic waves. A comprehensive parametric study examined the effects of various parameters including dielectric thickness, an external DC magnetic field, laser pulse length, driver beam radius, and total current, on the wakefield generated THz radiation. Through systematic variation of these parameters, the study aims to elucidate the controlled features of the resulting fields and optimize THz radiation.

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A. A. Molavi Choobini, F. M. Aghamir. 2025-01-21. Wakefield-induced THz wave generation in a hybrid dielectric-plasma cylindrical waveguide. https://arxiv.org/abs/2501.12042

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