Design and fabrication of distributed Bragg reflector multilayers for dynamic pressure sensing

Area of Science:

• Materials Science and Engineering
• Optoelectronics
• Nanotechnology

Background:

• Dynamic pressure sensing is crucial for understanding shock phenomena.
• Existing sensors face limitations in response time and spatial resolution.
• Photonic crystals offer unique opto-mechanical properties for sensing applications.

Purpose of the Study:

• To design and test a novel 2D-surface shock pressure sensor.
• To leverage 1D-Photonic Crystal (Distributed Bragg Reflector Multilayer - DBR/ML) structures for dynamic pressure sensing.
• To investigate material and device design for optimal response to dynamic loading.

Main Methods:

• Modeling and fabrication of DBR/ML structures with varying SiO_1.5/SiO_1.7 bilayer stacks.
• Investigation of structural and material effects on spectral and mechanical properties.
• Dynamic compressive loading experiments (~7.2 GPa) and optical spectral analysis.

Main Results:

• A 10-bilayer DBR/ML structure demonstrated a significant spectral blueshift (29 nm) under dynamic load.
• The sensor exhibited a rapid response time of approximately 5 nanoseconds.
• Observed response time is well within the shock pressure rise time measured by PDV velocimetry.

Conclusions:

• The feasibility of DBR/ML structures as dynamic pressure sensors is successfully demonstrated.
• The developed sensor offers potential for monitoring both temporal and spatial variations during shock compression.
• This technology presents a promising advancement in high-speed, high-pressure metrology.