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arXiv · 2301.04458

Femtosecond laser-induced sub-wavelength plasma inside dielectrics: III. Terahertz radiation emission

Kazem Ardaneh·Ken-Ichi Nishikawa·Remo Giust·Benoit Morel·Pierre-Jean Charpin·Arnaud Couairon·Guy Bonnaud·Francois Courvoisier
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Abstract

Electromagnetic radiation within the terahertz (THz) frequency range is of great interest for applications in remote sensing and time-domain spectroscopy. The laser-induced plasmas are promising mediums for generating THz radiation. It has been recently reported that focusing femtosecond Bessel pulses inside dielectrics induces a high aspect ratio over-critical plasmas. Here we show that the intense resonantly driven electrostatic fields at the so-called critical surface lead to THz radiation emission. Through three-dimensional particle-in-cell simulation and analytical derivation, we have investigated the emission of THz radiation. We show that the THz radiation is associated with a hot population of electrons trapped in ambipolar electric fields of the double layers.

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Kazem Ardaneh, Ken-Ichi Nishikawa, Remo Giust, Benoit Morel, Pierre-Jean Charpin, Arnaud Couairon, Guy Bonnaud, Francois Courvoisier. 2023-01-11. Femtosecond laser-induced sub-wavelength plasma inside dielectrics: III. Terahertz radiation emission. https://doi.org/10.1063/5.0126427

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