Random fiber laser based on a partial-reflection random fiber grating for high temperature sensing.

Area of Science:

• Photonics and Optical Engineering
• Sensing Technologies
• Materials Science

Background:

• Fiber lasers offer robust platforms for various applications.
• High-temperature sensing requires stable and reliable optical devices.
• Random fiber gratings provide unique spectral properties for laser design.

Purpose of the Study:

• To propose and demonstrate a stable single-wavelength random fiber laser (RFL) for high-temperature sensing.
• To investigate the use of a partial-reflection random fiber grating (PR-RFG) for laser stabilization.
• To evaluate the performance of the RFL in a wide temperature range.

Main Methods:

• Fabrication of a PR-RFG using a femtosecond laser.
• Design of the PR-RFG with a significantly higher primary reflection peak.
• Characterization of the RFL's stability, threshold, and temperature sensing capabilities.
• Theoretical calculations for PR-RFG reflectivity optimization (30%-90%).

Main Results:

• Demonstration of a stable, filter-free, single-wavelength RFL.
• Achieved a low lasing threshold of 6.4 mW.
• Successful temperature sensing from 25°C to 500°C.
• Obtained a high optical signal-to-noise ratio (SNR) of up to 70 dB.

Conclusions:

• The proposed PR-RFG is effective in ensuring the stability of a filter-free RFL.
• The developed RFL is suitable for high-temperature sensing applications.
• The PR-RFG design offers a promising approach for stable fiber laser development.