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arXiv · 2407.18579

Steering laser-produced THz radiation in air with superluminal ionization fronts

Silin Fu·Baptiste Groussin·Yi Liu·Andre Mysyrowicz·Vladimir Tikhonchuk·Aurelien Houard
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Abstract

We demonstrate that pulsed THz radiation produced in air by a focused ultrashort laser pulse can be steered to large angles or even in the backward direction with respect to the laser propagation axis. The emission angle is adjusted by the flying focus technique, which determines the speed and direction of the ionization front created by the single-color laser pulse. This easily adjustable THz source, being well separated from the intense laser, opens exciting applications for remote THz spectroscopy.

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Silin Fu, Baptiste Groussin, Yi Liu, Andre Mysyrowicz, Vladimir Tikhonchuk, Aurelien Houard. 2024-07-26. Steering laser-produced THz radiation in air with superluminal ionization fronts. https://doi.org/10.1103/physrevlett.134.045001 10.1103/physrevlett.134.045001 10.1103/physrevlett.134.045001

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