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arXiv · 2507.01530

Defects Potentials for Two-Dimensional Topological Materials

Yuval Abulafia·Amit Goft·Nadav Orion·Eric Akkermans
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Abstract

For non-topological quantum materials, introducing defects can significantly alter their properties by modifying symmetry and generating a nonzero analytical index, thus transforming the material into a topological one. We present a method to construct the potential matrix configuration with the purpose of obtaining a non-zero analytical index, akin to a topological invariant like a winding or Chern number. We establish systematic connections between these potentials, expressed in the continuum limit, and their initial tight-binding model description. We apply our method to graphene with an adatom, a vacancy, and both as key examples illustrating our comprehensive description. This method enables analytical differentiation between topological and non-topological zero-energy modes and allows for the construction of defects that induce topology.

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Yuval Abulafia, Amit Goft, Nadav Orion, Eric Akkermans. 2025-07-02. Defects Potentials for Two-Dimensional Topological Materials. https://arxiv.org/abs/2507.01530

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