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Axisymmetric scalable magneto-gravitational trap for diamagnetic particle levitation



Kristine A. Bertness, John P. Houlton, Max L. Chen, Matthew D. Brubaker, Charles T. Rogers


We report an axisymmetric magnetic trap design for levitating diamagnetic particles. The magnetic traps each consist of two iron pole pieces passively driven by a neodymium iron boron (NdFeB) permanent magnet. The magnetic field configuration between the pole pieces combined with the earth's gravitational field form a 3-D confining potential capable of levitating a range of diamagnetic substances, e.g. graphite powder, silica microspheres, and gallium nitride (GaN) powder and nanowires. Particles trap stably at atmosphere and in high-vacuum for periods up to weeks, largely determined by choices made to actively destabilize the trap. We describe the principles of operation, finite element design, approximate closed-form results for design rules, and examples of operation of such traps.
Review of Scientific Instruments


magnetic trap, particle levitation, gallium nitride nanowires


Bertness, K. , Houlton, J. , Chen, M. , Brubaker, M. and Rogers, C. (2018), Axisymmetric scalable magneto-gravitational trap for diamagnetic particle levitation, Review of Scientific Instruments, [online], (Accessed May 18, 2024)


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Created December 11, 2018, Updated December 19, 2019