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arXiv · 1703.10949

Broadband terahertz emission from two-color fs-laser-induced microplasmas

Illia Thiele·Pedro Gonzalez de Alaiza Martinez·Rachel Nuter·Alisee Nguyen·Luc Berge·Stefan Skupin
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Abstract

We investigate terahertz emission from two-color fs-laser-induced microplasmas. Under strongest focusing conditions, microplasmas are shown to act as point-sources for broadband terahertz-to-far-infrared radiation, where the emission bandwidth is determined by the plasma density. Semi-analytical modeling allows us to identify scaling laws with respect to important laser parameters. In particular, we find that the optical-to-THz conversion efficiency crucially depends on the focusing conditions. We use this insight to demonstrate by means of Maxwell-consistent 3D simulations, that for only 10-$\mu$J laser energy a conversion efficiency well above $10^{-4}$ can be achieved.

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Illia Thiele, Pedro Gonzalez de Alaiza Martinez, Rachel Nuter, Alisee Nguyen, Luc Berge, Stefan Skupin. 2017-03-31. Broadband terahertz emission from two-color fs-laser-induced microplasmas. https://doi.org/10.1103/physreva.96.053814

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