Narrowband THz Emission from a Plasma Oscillator Imbedded in a Plasma Density Gradient

Manoj Kumar; Bernhard Ersfeld; Jaeho Lee; Dohyun Park; Seungyun Kim; Inhyuk Nam; Minseok Kim; Seongjin Jeon; Dino A. Jaroszynski; Hyyong Suk; Min Sup Hur

arXiv · 2402.17267

Narrowband THz Emission from a Plasma Oscillator Imbedded in a Plasma Density Gradient

Manoj Kumar·Bernhard Ersfeld·Jaeho Lee·Dohyun Park·Seungyun Kim·Inhyuk Nam·Minseok Kim·Seongjin Jeon·Dino A. Jaroszynski·Hyyong Suk·Min Sup Hur

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Abstract

A novel method is presented for generating radiation using the beat wave associated with a bi-frequency laser pulse, to excite plasma oscillations in a plasma slab with a density gradient. By resonantly exciting a plasma wave, it can be localised and transformed into a plasma oscillator that produces a beam of radially polarised terahertz radiation. Particle-in-cell simulations and analytic theory are used to demonstrate its main characteristics, which includes narrow bandwidth. The radiator should have useful applications such as terahertz-band particle accelerators and pump-probe experiments.

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Manoj Kumar, Bernhard Ersfeld, Jaeho Lee, Dohyun Park, Seungyun Kim, Inhyuk Nam, Minseok Kim, Seongjin Jeon, Dino A. Jaroszynski, Hyyong Suk, Min Sup Hur. 2024-02-27. Narrowband THz Emission from a Plasma Oscillator Imbedded in a Plasma Density Gradient. https://arxiv.org/abs/2402.17267

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