Frequency-Stable Low-Threshold SBS-OEO for Precision Temperature Sensing in Electromagnetically Harsh Environments.

Area of Science:

• Photonics and Optical Sensing
• Electromagnetics and Microwave Engineering
• Materials Science and Engineering

Background:

• Traditional temperature sensing methods struggle in electromagnetically harsh environments.
• Optoelectronic oscillators (OEOs) offer potential for stable frequency generation.
• Stimulated Brillouin scattering (SBS) provides a mechanism for sensing based on material properties.

Purpose of the Study:

• To develop a precision temperature sensing system for electromagnetically harsh environments.
• To leverage a frequency-stable OEO with SBS for enhanced sensing capabilities.
• To improve vibration immunity and reduce the SBS power threshold in temperature sensing.

Main Methods:

• Utilized a low-threshold, frequency-stable optoelectronic oscillator (OEO).
• Employed stimulated Brillouin scattering (SBS) to create a temperature-dependent notch filter.
• Integrated a Faraday rotation mirror (FRM) for dual-pass SBS interaction, enhancing vibration immunity and reducing the SBS threshold.

Main Results:

• Achieved a temperature sensitivity of 1.0609 MHz/°C with R² = 0.999.
• Demonstrated long-term temperature stability of ±0.004 °C.
• Reduced the SBS power threshold by 2.7 dB through dual-pass SBS interaction.

Conclusions:

• The developed SBS-OEO system provides precise temperature sensing in challenging electromagnetic conditions.
• The integration of FRM significantly enhances vibration immunity and lowers the SBS threshold.
• This innovative approach offers superior performance compared to conventional SBS-OEO temperature sensing techniques.