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Updated: Nov 22, 2025
09:43
Optimized Setup and Protocol for Magnetic Domain Imaging with In Situ Hysteresis Measurement
Published on: November 7, 2017
9.7K
High homogeneity permanent magnet for diamond magnetometry.
Arne Wickenbrock1, Huijie Zheng1, Georgios Chatzidrosos1
1Helmholtz-Institut, GSI Helmholtzzentrum für Schwerionenforschung, 55128 Mainz, Germany; Johannes Gutenberg-Universität Mainz, Institute of Physics, 55128 Mainz, Germany.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|January 11, 2021
Summary
We designed and built a Halbach magnet array producing a highly homogeneous magnetic field for advanced imaging. This setup is ideal for sensitive diamond-based sensors in microwave-free applications.
Area of Science:
- Physics
- Magnetics
- Materials Science
Background:
- Halbach magnet arrays generate uniform magnetic fields with minimal stray fields.
- Homogeneous fields are crucial for precision measurements in scientific instruments.
Purpose of the Study:
- To design, construct, and characterize a Halbach magnet array for a diamond-based microwave-free widefield imaging setup.
- To achieve a highly homogeneous magnetic field within a specific volume.
Main Methods:
- Design and construction of a stack of two Halbach rings with a 10 cm inner diameter.
- Characterization of the magnetic field homogeneity using a novel fiberized diamond-based sensor.
- Utilizing a 3D translation stage for detailed sensor positioning during characterization.
Main Results:
- The Halbach magnet array successfully produced a homogeneous magnetic field of approximately 105 mT.
- Field homogeneity was measured to be less than 100 ppm over a 1.0×1.0×0.5 cm³ volume.
- Characterization confirmed the array's suitability for the intended widefield imaging application.
Conclusions:
- The constructed Halbach magnet array meets the stringent homogeneity requirements for advanced imaging.
- The system is well-suited for use in diamond-based microwave-free widefield imaging.
- This work demonstrates a practical application of Halbach arrays in sensitive scientific instrumentation.
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