Highly-sensitive gas pressure sensor using twin-core fiber based in-line Mach-Zehnder interferometer

Area of Science:

• Optics and Photonics
• Fiber Optic Sensors
• Materials Science

Background:

• Mach-Zehnder interferometers are sensitive to external perturbations.
• Twin-core fibers offer a unique platform for creating compact interferometric devices.
• Accurate gas pressure sensing is crucial in various industrial and environmental applications.

Purpose of the Study:

• To propose and experimentally demonstrate a novel Mach-Zehnder interferometer for gas pressure measurements.
• To investigate the performance of a twin-core fiber based interferometer for sensing applications.
• To develop an ultra-compact and highly sensitive gas pressure sensor.

Main Methods:

• Fabrication of an in-line Mach-Zehnder interferometer by splicing a twin-core fiber section between single-mode fibers.
• Creation of a micro-channel using a femtosecond laser to form one interferometer arm.
• Utilizing the intact core as the reference arm for interference.

Main Results:

• The fabricated interferometer exhibited a high gas pressure sensitivity of -9.6 nm/MPa.
• A low temperature cross-sensitivity of 4.4 KPa/°C was achieved.
• The device demonstrated an ultra-compact size and an all-fiber configuration.

Conclusions:

• The twin-core fiber Mach-Zehnder interferometer is a promising technology for highly-sensitive gas pressure sensing.
• The sensor's compact size and robustness make it suitable for deployment in harsh environments.
• This approach offers a viable alternative to existing gas pressure sensing technologies.