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arXiv · 1802.09420

Multiferroic Micro-Motors with Deterministic Single Input Control

John P. Domann·Cai Chen·Abdon E. Sepulveda·Rob N. Candler·Greg P. Carman
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Abstract

This paper describes a method for achieving continuous deterministic 360$^{\circ} $ magnetic moment rotations in single domain magnetoelastic discs, and examines the performance bounds for a mechanically lossless multiferroic bead-on-a-disc motor based on dipole coupling these discs to small magnetic nanobeads. The continuous magnetic rotations are attained by controlling the relative orientation of a four-fold anisotropy (e.g., cubic magnetocrystalline anisotropy) with respect to the two-fold magnetoelastic anisotropy. This approach produces continuous rotations from the quasi-static regime up through operational frequencies of several GHz. Driving strains of only $\approx$90 to 180 ppm are required for operation of motors using existing materials. The large operational frequencies and small sizes, with lateral dimensions of $\approx$100s of nanometers, produce large power densities for the rotary bead-on-a-disc motor, and a newly proposed linear variant, in a size range where power dense alternative technologies do not currently exist.

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John P. Domann, Cai Chen, Abdon E. Sepulveda, Rob N. Candler, Greg P. Carman. 2018-02-26. Multiferroic Micro-Motors with Deterministic Single Input Control. https://arxiv.org/abs/1802.09420

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