Magnetic Moment vs Angular Momentum: Spin Hall Response in Bismuth

Junji Fujimoto; Yuki Izaki; Yuki Fuseya

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arXiv · 2508.07200

Magnetic Moment vs Angular Momentum: Spin Hall Response in Bismuth

Junji Fujimoto·Yuki Izaki·Yuki Fuseya

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Abstract

Spin currents can carry either spin angular momentum or its associated magnetic moment, which are no longer strictly proportional in multiband systems. Using a multiband $k \cdot p$ model, we compute the intrinsic spin Hall conductivity tensors of elemental Bi. The magnetic-moment tensor emerges about two orders of magnitude larger and far less anisotropic than the angular-momentum tensor, while quasiparticle damping activates otherwise longitudinal components. The magnetic-moment spin Hall angle exceeds unity, demonstrating that a clear distinction between the two currents is indispensable for multiband systems.

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Junji Fujimoto, Yuki Izaki, Yuki Fuseya. 2025-08-10. Magnetic Moment vs Angular Momentum: Spin Hall Response in Bismuth. https://arxiv.org/abs/2508.07200

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