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arXiv · 2410.22251

Bloch classification surface for three-band systems

Gilles Abramovici
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Abstract

Topologically protected states can be found in physical systems, that show singularities in some energy contour diagram. These singularities can be characterized by winding numbers, defined on a classification surface, which maps physical state parameters. We have found a classification surface, which applies for three-band hamiltonian systems in the same way than standard Bloch surface does for two-band ones. This generalized Bloch surface is universal in the sense that it classifies a very large class of three-band systems, which we have exhaustively studied, finding specific classification surfaces, applying for each one.

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Gilles Abramovici. 2024-10-29. Bloch classification surface for three-band systems. https://doi.org/10.1088/1402-4896%2Fad8b82

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