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arXiv · 2203.12541

Unconventional Surface State Pairs in a High-Symmetry Lattice with Anti-ferromagnetic Band-folding

L. -L. Wang·J. Ahn·R. -J. Slager·Y. Kushnirenko·B. G. Ueland·A. Sapkota·B. Schrunk·B. Kuthanazhi·R. J. McQueeney·P. C. Canfield·A. Kaminski
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Abstract

Many complex magnetic structures in a high-symmetry lattice can arise from a superposition of well-defined magnetic wave vectors. These "multi-q" structures have garnered much attention because of interesting real-space spin textures such as skyrmions. However, the role multi-q structures play in the topology of electronic bands in momentum space has remained rather elusive. Here we show that the type-I anti-ferromagnetic 1q, 2q and 3q structures in an face-centered cubic sublattice with band inversion, such as NdBi, can induce unconventional surface state pairs inside the band-folding hybridization bulk gap. Our density functional theory calculations match well with the recent experimental observation of unconventional surface states with hole Fermi arc-like features and electron pockets below the Neel temperature. We further show that these multi-q structures have Dirac and Weyl nodes. Our work reveals the special role that band-folding from anti-ferromagnetism and multi-q structures can play in developing new types of surface states.

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L. -L. Wang, J. Ahn, R. -J. Slager, Y. Kushnirenko, B. G. Ueland, A. Sapkota, B. Schrunk, B. Kuthanazhi, R. J. McQueeney, P. C. Canfield, A. Kaminski. 2022-03-23. Unconventional Surface State Pairs in a High-Symmetry Lattice with Anti-ferromagnetic Band-folding. https://doi.org/10.1038/s42005-023-01180-6

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