Angular Momentum Transfer in Magnetic Weyl Semimetal Spheres

Adriano Biondo; Francesco M. D. Pellegrino

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arXiv · 2607.27086

Angular Momentum Transfer in Magnetic Weyl Semimetal Spheres

Adriano Biondo·Francesco M. D. Pellegrino

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Abstract

In this work, we investigate the problem of electromagnetic angular momentum within the framework of topological materials, described by axion electrodynamics. Specifically, we calculate the electromagnetic angular momentum for a spherical sample of magnetic Weyl semimetal in the presence of a point charge. We then analyze how, by moving the point charge quasi-statically, the angular momentum stored in the electromagnetic field can be converted into mechanical angular momentum of the sphere. Finally, we derive analytical expressions for the resulting angular velocity and angular displacement, demonstrating that the effect is enhanced in the Weyl semimetal compared with a topological insulator.

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Adriano Biondo, Francesco M. D. Pellegrino. 2026-07-29. Angular Momentum Transfer in Magnetic Weyl Semimetal Spheres. https://arxiv.org/abs/2607.27086

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