Time-Resolved Interferometric Measurements of Plasma Density Evolution in Laser-Driven Capacitor-Coil Targets

TL;DR

This study presents time-resolved interferometric measurements of plasma density evolution in laser-driven capacitor-coil targets, revealing plasma sources and providing data crucial for designing magnetized high-energy-density plasma experiments.

Contribution

It offers the first direct, time-resolved measurements of plasma density around capacitor-coil targets, enhancing understanding of plasma loading and evolution in such systems.

Findings

Identified two distinct plasma sources in the coil region.

Provided quantitative electron density maps over time.

Revealed plasma dynamics relevant for experimental design.

Abstract

Laser-driven capacitor-coil targets provide a compact platform for generating strong magnetic fields and are widely used in magnetized high-energy-density plasma experiments. In addition to magnetic-field generation, these targets also produce plasma in the coil region, which can influence the subject physical processes, interact with secondary targets or external plasmas in their applications. However, direct, time-resolved measurements of the plasma density surrounding the coil remain limited. Here, we report interferometric measurements of the plasma density evolution in laser-driven capacitor-coil targets irradiated by the University of Osaka LFEX laser. Two-dimensional electron density maps reveal two distinct plasma sources loading the coil region: plasma generated in the coil itself and plasma produced by laser ablation of the target plates. These results provide quantitative information on plasma loading and evolution in capacitor-coil targets and are directly relevant to the design and modeling of magnetized high-energy-density plasma experiments.