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arXiv · 2003.08899

Highly-efficient terahertz radiation generated by surface electrons from laser-foil interactions

Ke Hu·Longqing Yi
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Abstract

A novel scheme for generating powerful terahertz (THz) radiation based on laser-solid interactions is proposed. When a $p$-polarized femtosecond laser impinges obliquely on a plane solid target and the target partially blocks the laser energy, surface electrons are extracted out and accelerated by the laser fields, forming a low-divergence electron beam. A half-cycle THz radiation pulse is emitted simultaneously as the beam passes by the edge of the target, due to coherent diffraction radiation. Our particle-in-cell simulations show that the relativistic THz pulse can have an energy of a few tens of millijoule and the conversion efficiency can be over 1$\%$ with existing $\sim$J level femtosecond laser sources.

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Ke Hu, Longqing Yi. 2020-03-19. Highly-efficient terahertz radiation generated by surface electrons from laser-foil interactions. https://doi.org/10.1103/physreva.102.023530

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