Revealing the Dominance of the Orbital Hall Effect over Spin in Transition Metal Heterostructures

J. L. Costa; E. Santos; J. B. S. Mendes; A. Azevedo

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arXiv · 2506.08425

Revealing the Dominance of the Orbital Hall Effect over Spin in Transition Metal Heterostructures

J. L. Costa·E. Santos·J. B. S. Mendes·A. Azevedo

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Abstract

We study inverse spin and orbital Hall effects in 19 transition metals using spin-pumping driven by ferromagnetic resonance. Spin-to-charge conversion was measured in YIG/X(5), while orbital-to-charge conversion was probed in YIG/Pt(2)/X(5) heterostructures. Here, X represents the different transition metals. Surprisingly, the orbital contribution overwhelmingly dominates over the spin response, clarifying the challenge of disentangling these effects. Our results largely agree with first-principles predictions for spin and orbital Hall conductivities but reveal discrepancies in select materials. These findings emphasize the fundamental role of the orbital Hall effect, and position orbitronics as a pivotal frontier in condensed matter physics.

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J. L. Costa, E. Santos, J. B. S. Mendes, A. Azevedo. 2025-06-10. Revealing the Dominance of the Orbital Hall Effect over Spin in Transition Metal Heterostructures. https://arxiv.org/abs/2506.08425

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