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Updated: Aug 6, 2026
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Experimental Methods for Trapping Ions Using Microfabricated Surface Ion Traps
Published on: August 17, 2017
Development of a high-performance permanent magnet system for ion trapping experiments
Jifei Wu1,2, Jiawei Wang1,2, Tianhang Zhang1,2
1Institute of Modern Physics, Fudan University, Shanghai 200433, China.
The Review of Scientific Instruments
|July 17, 2026
Summary
A novel compact permanent magnet achieves a 0.8 T central field with 99.988% uniformity. This cost-effective, cryogenics-free design offers an alternative to superconducting magnets for ion traps and mass spectrometry.
Area of Science:
- Physics, Applied Physics
- Materials Science, Magnetic Materials
Background:
- Superconducting magnets are essential for high-field applications but require cryogenics and external power.
- Developing compact, high-performance permanent magnets is crucial for cost-effective and accessible scientific instrumentation.
Purpose of the Study:
- To design and fabricate a compact permanent magnet system.
- To achieve high magnetic field strength and uniformity for specialized applications.
- To provide a viable, cost-effective alternative to superconducting magnets.
Main Methods:
- Optimized stacking of fifteen Neodymium-Iron-Boron (NdFeB) rings.
- Tunable North-South-South-North (NS-SN-NS) magnetic configuration.
- Finite element analysis for field reconstruction and uniformity assessment.
Main Results:
- A central magnetic field of 0.8 Tesla was generated.
- A magnetic field uniformity of 99.988% was achieved within a 1 mm radius spherical volume.
- Radial dipole components were identified as the primary source of field inhomogeneity.
Conclusions:
- The designed permanent magnet offers a high-performance, cryogenics-free solution.
- This compact magnet is a cost-effective alternative for ion-trap development and Fourier-transform ion cyclotron resonance mass spectrometry.
- The NS-SN-NS configuration demonstrates effective field generation and uniformity control.
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