Microdroplet target synthesis for kilohertz ultrafast lasers

TL;DR

This paper presents a novel method for creating stable, micron-scale liquid targets at kilohertz repetition rates using femtosecond laser pulses, enabling advanced applications in ultrafast laser experiments.

Contribution

It introduces a technique to produce micron-scale liquid targets with high stability and reproducibility at kilohertz rates, suitable for air and vacuum environments.

Findings

Produced 2.1 μm water droplets with <0.3 μm shot-to-shot variation

Achieved features like 1.3 μm necks with high precision

Demonstrated potential for improved laser-cluster and ion acceleration experiments

Abstract

We have developed a method for producing spatially stable micron-scale liquid targets of flexible shapes at kilohertz repetition rate for use in air and vacuum, by perturbing 5 and 30 \mu m diameter streams with femtosecond laser pulses and monitoring the temporal development of the perturbation. Using water, we have produced features such as 2.1 \mu m diameter droplet and 1.3 \mu m diameter neck with less than 0.3 \mu m shot-to-shot variation, with prospects for further reduction in size and variability. The use of such micron-scale targets can be expected to prevent conductive heat dissipation, enhance field strength for ion acceleration and allow spatially-deterministic laser-cluster experiments.