MIM waveguide optical accelerometer designed with a biomimetic radial stress structure inspired by spider webs

Area of Science:

• Nanotechnology
• Optical Engineering
• Materials Science

Background:

• Inertial sensing is crucial for navigation and motion tracking.
• Existing accelerometers face limitations in sensitivity, size, and thermal stability.
• Optical methods offer potential for high-precision sensing but require innovative designs.

Purpose of the Study:

• To develop and validate a novel optical accelerometer.
• To leverage a spider-web-inspired topology for enhanced sensitivity and multi-axis readout.
• To integrate metal-insulator-metal (MIM) waveguides for efficient optical transduction.

Main Methods:

• Design and simulation of a radial-stress topology with a central proof mass and hexagonal cavity.
• Embedding MIM waveguides at strain hot spots to excite Fano resonances.
• Utilizing finite element method (FEM) simulations for optical mode analysis and calibration.
• Testing thermal stability across a range of temperatures (273.15 K to 373.15 K).

Main Results:

• Demonstrated two-dimensional readout with distinct resonances for x-axis (1104 nm) and y-axis (859 nm) detection.
• Achieved high sensitivities: 0.0228 nm/g for x-axis and 0.1731 nm/g for y-axis.
• Exhibited excellent thermal stability with minimal peak drift and linewidth changes from 273.15 K to 373.15 K.
• Validated high Q-factors and figure of merit (FOM) for both axes.

Conclusions:

• The bio-inspired optical accelerometer achieves multi-axis decoupling and compact manufacturability.
• Deep integration of topology and MIM resonances enables high Q-factor and low noise operation.
• The device presents a scalable route towards high-performance, nanoscale optical inertial sensing.