Apparatus to control and visualize the impact of a high-energy laser pulse on a liquid target

TL;DR

This paper introduces an experimental setup that precisely controls and visualizes how a liquid target responds to high-energy laser pulses, enabling detailed studies of laser-induced vaporization effects.

Contribution

The novel apparatus combines beam-shaping and high-speed imaging to control and observe laser-liquid interactions across multiple timescales with high spatial resolution.

Findings

Liquid motion is fully controlled by laser energy distribution.

The setup allows spatiotemporal resolution of vaporization dynamics.

Potential for detailed laser-matter interaction studies.

Abstract

We present an experimental apparatus to control and visualize the response of a liquid target to a laser-induced vaporization. We use a millimeter-sized drop as target and present two liquid-dye solutions that allow a variation of the absorption coefficient of the laser light in the drop by seven orders of magnitude. The excitation source is a Q-switched Nd:YAG laser at its frequency-doubled wavelength emitting nanosecond pulses with energy densities above the local vaporization threshold. The absorption of the laser energy leads to a large-scale liquid motion at timescales that are separated by several orders of magnitude, which we spatiotemporally resolve by a combination of ultra-high-speed and stroboscopic high-resolution imaging in two orthogonal views. Surprisingly, the large-scale liquid motion at upon laser impact is completely controlled by the spatial energy distribution obtained by a precise beam-shaping technique. The apparatus demonstrates the potential for accurate and quantitative studies of laser-matter interactions.