Pump with broadband probe experiments for single-shot measurements of plasma conditions and crossed-beam energy transfer

TL;DR

This paper introduces a single-shot, broadband probe laser technique for measuring plasma conditions with high sensitivity, enabling rapid, non-perturbative diagnostics crucial for inertial confinement fusion research.

Contribution

It experimentally demonstrates a novel method using crossed-beam energy transfer for plasma diagnostics, significantly improving sensitivity over traditional Thomson scattering.

Findings

Achieved single-shot measurement of plasma parameters.

Signal enhancement over 9 orders of magnitude compared to Thomson scattering.

Applicable to inertial confinement fusion conditions.

Abstract

A novel technique for measuring plasma conditions using monochromatic pump-broadband probe laser interactions has been experimentally demonstrated. Originally proposed in [J. Ludwig et al., Phys. Plasmas \textbf{26}, 113108 (2019)], this method utilizes crossed-beam energy transfer between the broadband probe and the pump, mediated by plasma ion acoustic waves. The complete energy transfer spectrum can be captured in a single shot, enabling the inference of plasma parameters such as density, electron and ion temperatures, and flow velocity. Compared to Thomson scattering, this technique offers signal enhancements typically larger than 9 orders of magnitude, significantly reducing the required probe laser intensity and facilitating interactions that are linear and measurements that are non-perturbative of the plasma. Furthermore, it provides a powerful tool for advancing studies of crossed-beam energy transfer under conditions relevant to inertial confinement fusion experiments.