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arXiv · 2310.09310

Weyl points and spin-orbit coupling in copper-substituted lead phosphate apatite

Martin Braß·Liang Si·Karten Held
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Abstract

We study the impact of spin-orbit coupling on the topological band-properties of copper-substituted lead phosphate apatite using a combination of group-theoretical analysis and full-relativistic density-functional theory calculations. We characterize Weyl points at time-reversal invariant momenta and find that a band-inversion due to spin-orbit coupling leads to additional Weyl points close to the Fermi-edge at general momenta. To determine the position of the altogether 66 Weyl points in the Brilouin-zone, we develop an algorithm that follows a Berry-curvature-derived vector field to its monopole: the Weyl point. The emerging surface Fermi-arcs and their spin-polarization reveal avoided crossings and a Fermi-loop detached from the Weyl points.

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Martin Braß, Liang Si, Karten Held. 2023-10-12. Weyl points and spin-orbit coupling in copper-substituted lead phosphate apatite. https://arxiv.org/abs/2310.09310

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