Broadband Terahertz Wave Emission from Liquid Metal

TL;DR

This paper demonstrates broadband terahertz wave emission from flowing liquid metal, specifically gallium, excited by sub-picosecond laser pulses, showing promise as a high-power THz source with broader bandwidth than water.

Contribution

It introduces a novel liquid metal-based method for generating broadband THz waves, avoiding surface debris issues associated with solid metals.

Findings

Liquid gallium emits stronger, broader THz signals than water.

Liquid metals can serve as efficient, high-repetition-rate THz sources.

Potential for high-power THz applications with liquid metal emitters.

Abstract

Metals have been studied as terahertz sources for decades. Recent research has shown the potential of metals in generating extremely high THz pulse energy excited by intense laser pulses. To avoid the metal surface debris caused by laser pulses, here, we report the results of the broadband terahertz wave emission from a flowing liquid metal line excited by sub-picosecond laser pulses. The THz signal emitted from the liquid gallium line shows stronger field with broader bandwidth comparing with the signal from water under the identical optical excitation conditions. Our preliminary study suggests that the liquid metals have the potential to serve as efficient and powerful THz sources for the intense lasers with a high repetition rate.