Abstract-Terahertz emission from laser-driven gas-plasmas: a plasmonic point of view

I. Thiele, B. Zhou, A. Nguyen, E. Smetanina, R. Nuter, P. González de Alaiza Martínez, K. J. Kaltenecker, J. Déchard, L. Bergé, P. U. Jepsen, S. Skupin

https://arxiv.org/abs/1803.06889

We investigate terahertz generation in two-color laser-induced gas plasmas. Resonances attributed to plasmonic effects are shown to broaden the emission spectra significantly, when electrons are excited along a direction where the plasma size is smaller than the plasma wavelength. We demonstrate that such resonances can be turned on and off by changing the polarization properties of elliptically-shaped driving laser-pulses. Both 3D Maxwell consistent simulations and experimental results confirm that a significant THz pulse shortening and spectral broadening can be achieved by exploiting the transverse driving laser-beam shape as an additional degree of freedom.