Boosted High Order Harmonics from Electron Density Singularity Formed at the Relativistic Laser Bow Wave

Jie Mu; Timur Zh. Esirkepov; Yanjun Gu; Tae Moon Jeong; Petr Valenta; Alexander S. Pirozhkov; James K. Koga; Masaki Kando; Georg Korn; Sergei V. Bulanov

arXiv · 1904.05574

Boosted High Order Harmonics from Electron Density Singularity Formed at the Relativistic Laser Bow Wave

Jie Mu·Timur Zh. Esirkepov·Yanjun Gu·Tae Moon Jeong·Petr Valenta·Alexander S. Pirozhkov·James K. Koga·Masaki Kando·Georg Korn·Sergei V. Bulanov

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Abstract

We demonstrate coherent hard electromagnetic radiation generation from reflection by the electron density singularity formed at the relativistic bow wave in laser plasma via particle-in-cell simulations. Wake and bow waves driven by an intense laser pulse form an electron density singularity at the laser pulse front where they join. A counter-propagating laser pulse is reflected at the electron density modulations moving with relativistic velocity. The reflected electromagnetic pulse is compressed and its frequency is upshifted. Its frequency spectrum contains relativistic harmonics of the driver pulse frequency generated at the bow wave front, all upshifted with the same factor as the fundamental mode of the incident light.

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Jie Mu, Timur Zh. Esirkepov, Yanjun Gu, Tae Moon Jeong, Petr Valenta, Alexander S. Pirozhkov, James K. Koga, Masaki Kando, Georg Korn, Sergei V. Bulanov. 2019-04-11. Boosted High Order Harmonics from Electron Density Singularity Formed at the Relativistic Laser Bow Wave. https://arxiv.org/abs/1904.05574

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