Temperature sensor based on a hybrid ITO-silica resonant cavity

Area of Science:

• Integrated optical devices
• Materials science
• Nanophotonics

Background:

• Polymer-dielectric and polymer-semiconductor systems dominate integrated optical devices.
• Polymers exhibit limited environmental stability, restricting device longevity and performance.
• There is a need for more robust and stable materials in optical sensing.

Purpose of the Study:

• To fabricate and characterize a novel hybrid optical device.
• To investigate the optical properties of an indium tin oxide (ITO) coating on a silicon dioxide toroidal resonant cavity.
• To evaluate the device's performance as a temperature sensor.

Main Methods:

• Fabrication of a hybrid device with an ITO coating on a silicon dioxide toroidal resonant cavity.
• Finite element method (FEM) simulations to analyze the optical field distribution.
• Experimental measurement of the optical quality factor.
• Characterization of the device's performance as a temperature sensor.

Main Results:

• The high-index ITO film significantly alters the optical mode profile.
• The device's quality factor is limited by material loss.
• The hybrid temperature sensor shows a nearly 3-fold improvement in performance.
• High thermo-optic coefficient of ITO and field localization enhance sensing capabilities.

Conclusions:

• Hybrid devices integrating ITO with silicon dioxide offer superior performance.
• The fabricated device demonstrates enhanced temperature sensing capabilities.
• This approach provides a pathway for developing robust and high-performance optical sensors.