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arXiv · 2305.04945

Non-Abelian hyperbolic band theory from supercells

Patrick M. Lenggenhager·Joseph Maciejko·Tomáš Bzdušek
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Abstract

Wave functions on periodic lattices are commonly described by Bloch band theory. Besides Abelian Bloch states labeled by a momentum vector, hyperbolic lattices support non-Abelian Bloch states that have so far eluded analytical treatments. By adapting the solid-state-physics notions of supercells and zone folding, we devise a method for the systematic construction of non-Abelian Bloch states. The method applies Abelian band theory to sequences of supercells, recursively built as symmetric aggregates of smaller cells, and enables a rapidly convergent computation of bulk spectra and eigenstates for both gapless and gapped tight-binding models. Our supercell method provides an efficient means of approximating the thermodynamic limit and marks a pivotal step towards a complete band-theoretic characterization of hyperbolic lattices.

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Patrick M. Lenggenhager, Joseph Maciejko, Tomáš Bzdušek. 2023-05-08. Non-Abelian hyperbolic band theory from supercells. https://doi.org/10.1103/physrevlett.131.226401

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