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arXiv · 2503.21063

Gapless Topological Peierls-like instabilities in more than one dimension

Santiago Palumbo·Pablo S. Cornaglia·Jorge I. Facio
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Abstract

A periodic lattice distortion that reduces the translational symmetry folds electron bands into a reduced Brillouin zone, leading to band mixing and a tendency to gap formation, as in the Peierls transition in one-dimensional systems. However, in higher dimensions, the resulting phase can present topological obstructions preventing a complete gap opening. We discuss two different mechanisms for such obstructions, emergent Weyl nodes and symmetry protected band crossings. Based on density-functional calculations, we show these mechanisms are at play in trigonal PtBi$_2$.

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Santiago Palumbo, Pablo S. Cornaglia, Jorge I. Facio. 2025-03-27. Gapless Topological Peierls-like instabilities in more than one dimension. https://doi.org/10.1103/x6zl-t5hs

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