Topological phase transition driven by structural defects

Andrii Syrota; Andrej Mesaros; Pascal Simon

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arXiv · 2609.26586

Topological phase transition driven by structural defects

Andrii Syrota·Andrej Mesaros·Pascal Simon

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Abstract

Structural defects, such as disclinations and dislocations, destroy the long-range crystalline order as they proliferate. In this work, we continuously drive a system from a crystalline state on a decorated honeycomb lattice to a hyperuniform amorphous state, by consecutively introducing Stone-Wales (SW) defects, which can be viewed as dipoles of dislocations. Using a topological Weaire-Thorpe Hamiltonian model to describe electrons in this system, we demonstrate that SW defects can cause pseudo-band inversions and, correspondingly, a reversal of the Chern number. Using adiabatic arguments and a computationally efficient spillage indicator, we predict the topological phase diagram of the amorphous state from the crystalline one. We explain the nature of the pseudo-band inversion through the renormalization of the hopping in an effective Hamiltonian based on a single SW defect.

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Andrii Syrota, Andrej Mesaros, Pascal Simon. 2026-09-22. Topological phase transition driven by structural defects. https://arxiv.org/abs/2609.26586

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