Key points
- LLNL scientists developed SAPPHIRE, a new diagnostic tool for observing plasma evolution.
- SAPPHIRE captures a complete plasma evolution with a single laser shot, achieving 100 billion frames per second.
- The technique utilizes a “chirped” laser pulse to record both temporal and spatial information simultaneously.
- SAPPHIRE overcomes limitations of traditional methods by eliminating errors from multiple laser shots.
Scientists at Lawrence Livermore National Laboratory (LLNL) have made a groundbreaking advancement in plasma diagnostics with the development of SAPPHIRE (Single-shot Advanced Plasma Probe Holographic Reconstruction). Published in Optica, the innovative technology allows researchers to capture the evolution of high-density plasmas with unprecedented detail, recording at an astounding 100 billion frames per second using a single laser shot.
Traditional methods require multiple laser shots, introducing errors due to the inherently unstable and unpredictable nature of plasmas. SAPPHIRE eliminates this issue, providing a far more accurate and comprehensive view of plasma dynamics.
The key to SAPPHIRE lies in its use of a “chirped” laser pulse. This technique stretches the laser pulse in time, with different wavelengths of light (colors) arriving at different times. One half of the beam passes through the plasma, while the other half serves as a reference.
The interaction of these beams creates an interference pattern which, through sophisticated mathematical analysis, is translated into a detailed map of the plasma’s electron density over time. This process effectively creates a “movie” of the plasma’s evolution, revealing ultrafast phenomena previously hidden from view.
Lead author Liz Grace emphasizes the significance of this advancement, stating that previous methods only allowed for a single image per laser shot. The ability to capture the entire process in a single shot is crucial for understanding the complex, rapid changes within these high-energy systems. The implications for various fields are substantial, impacting our understanding of fundamental plasma physics and enabling advancements in related technologies.
The research team successfully tested SAPPHIRE on helium-nitrogen gas jets, but its potential applications extend far beyond. Grace envisions the use of SAPPHIRE in fusion energy research, particularly in Z-pinch plasmas, as well as in areas such as pulsed power systems, plasma optics, and laser-based particle accelerators.
The team has published a comprehensive guide on how to replicate the technology, opening up opportunities for further innovation and widespread application across diverse scientific disciplines.
