Fiber-optic Faraday-effect magnetic-field sensor based on flux concentrators

Area of Science:

• Optoelectronics
• Magnetometry
• Materials Science

Background:

• Fiber-optic sensors offer remote and non-intrusive measurement capabilities.
• Accurate magnetic field sensing is crucial in various scientific and industrial applications.
• Yttrium-iron-garnet (YIG) exhibits favorable magneto-optic properties for sensing.

Purpose of the Study:

• To describe the design and performance of a novel fiber-optic Faraday-effect magnetic-field sensor.
• To optimize sensitivity using flux concentrators and a YIG sensing element.
• To evaluate the sensor's noise equivalent field and bandwidth.

Main Methods:

• Utilized a fiber-optic Faraday-effect sensor configuration.
• Employed polarization-rotated reflection with a single polarization-maintaining optical fiber.
• Integrated ferrite flux concentrators magnetically coupled to a YIG sensing element.
• Characterized sensor performance, including noise equivalent field and bandwidth.

Main Results:

• The sensor design successfully integrated a YIG element with ferrite flux concentrators.
• The system demonstrated a noise equivalent field of 6 pT/√Hz.
• A 3-dB bandwidth of approximately 10 MHz was achieved.

Conclusions:

• The developed fiber-optic sensor provides sensitive and broadband magnetic field detection.
• The design leveraging YIG and flux concentrators is effective for enhancing sensor performance.
• This sensor technology holds promise for advanced magnetometry applications.