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1. Manganese-based permanent magnet materials

   https://doi.org/10.1016/j.pmatsci.2021.100872  

   Keller, Thomas; Baker, Ian (February 2022, Progress in Materials Science)
2. Harmonic Utilization Permanent Magnet Topology Design Considerations

   https://doi.org/10.1109/ICECET58911.2023.10389458  

   Madovi, Orwell; Khoshoo, Bhuvan; Foster, Shanelle N. (November 2023, IEEE)
3. Feedback Stabilization of a Permanent Magnet Levitation System

   https://doi.org/10.23919/ACC53348.2022.9867393  

   Shariatmadari, M. Reza; Komaee, Arash (June 2022, 2022 American Control Conference (ACC))

   A magnetic levitation system consists of a magnet facing groundward to attract a magnetic object against gravity and levitate it at a distance from the face of magnet. Due to the unstable nature of this system, it must be stabilized by means of feedback control, which adjusts the magnetic force applied to the levitating object depending on its measured position and possibly velocity. Conventionally, electromagnets have been used for magnetic levitation, as they can be simply controlled via their terminal voltages. This paper, however, studies a levitation system relying on a permanent magnet and a linear servomotor to control the applied magnetic force by changing the distance between the magnet and the levitating object. For the proposed system, which is highly nonlinear, a stabilizing feedback control law is developed using feedback linearization and other control design tools. Then, the closed-loop stability is examined against system parameters such as the size of the levitating object, the viscosity of the medium it moves in, and certain characteristics of the magnet in use. The emphasis here is on understanding the impact of intrinsic servomotor limitations, particularly its finite slew rate (cap on its maximum velocity), on the ability of feedback control to stabilize the closed-loop system. This particular limitation seems to be a major concern in utilizing permanent magnets for noncontact actuation and control. 

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4. MnBi ₂ Is a Permanent Magnet

   https://doi.org/10.1021/jacs.5c06874  

   Badding, Catherine K; Riesel, Eric A; Murphy, Ryan A; Puggioni, Danilo; Popov, Dmitry; Fabbris, Gilberto; Haskel, Daniel; Rondinelli, James M; Altman, Alison B; Freedman, Danna E (July 2025, Journal of the American Chemical Society)
5. Low-Power ULF Transmitter Design Using Static Permanent Magnet

   https://doi.org/10.23919/USNC-URSINRSM66067.2025.10907169  

   Chinnakkagari, Shashank; Manteghi, Majid (January 2025, IEEE)

   This paper presents a low-power Ultra Low Frequency (ULF) transmitter design that uses a static, permanent magnet to bring the surrounding magnetic shield near saturation. A low-power control coil modulates this static magnetic field by toggling sections of the shield between saturated and unsaturated states. The transmitter, operating at 400 Hz and tested using a 3D magnetometer, demonstrated an increase of 22.3 dB along the pole at 800 Hz and a 17.7 dB increase at 400 Hz perpendicular to the pole, with a further 33 dB enhancement than the control coil’s leakage at 800 Hz. These results highlight a novel method for efficient magnetic field modulation with significantly lower power requirements than traditional approaches. This novel approach reduces power consumption and opens new possibilities for designing scalable, energy-efficient ULF communication systems, with potential applications in underwater communication, remote sensing, and long-range wireless networks. 

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