Characterization of laser-driven shock waves in solids using a fiber optic pressure probe

Area of Science:

• Materials Science
• Optics and Photonics
• High-Pressure Physics

Background:

• Accurate measurement of transient pressures is crucial for understanding material response under extreme conditions.
• Laser-driven shock waves offer a method to generate such conditions in materials like polymethyl methacrylate (PMMA).

Purpose of the Study:

• To demonstrate the measurement of laser-driven shock wave pressure in PMMA using fiber optic pressure probes.
• To compare the performance of three distinct fiber optic sensor types for shock wave detection.

Main Methods:

• Shock waves were generated by focusing a high-power laser onto a thin foil target adjacent to PMMA blocks.
• Three fiber optic probes were employed: fiber Fabry-Perot, fiber Bragg grating, and interferometric fiber tip sensors.
• Shadowgraphy was used as a complementary technique for pressure estimation.

Main Results:

• The fiber Fabry-Perot sensor demonstrated capability in resolving the shock front with a rise time of 91 ns.
• Peak shock wave pressure was estimated to be approximately 3.4 GPa.
• Comparison of sensor performance in detecting shock wave dynamics was conducted.

Conclusions:

• Fiber optic sensors, particularly the fiber Fabry-Perot type, are viable tools for measuring laser-induced shock waves in PMMA.
• The study validates a method for in-situ pressure measurement under high-energy laser-matter interactions.