Topological transition induced by selective random defects on a honeycomb lattice

Sogen Ikegami; Kiyu Fukui; Shun Okumura; Yasuyuki Kato; Yukitoshi Motome

doi:10.1103/7n4x-d4nb

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arXiv · 2511.14134

Topological transition induced by selective random defects on a honeycomb lattice

Sogen Ikegami·Kiyu Fukui·Shun Okumura·Yasuyuki Kato·Yukitoshi Motome

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Abstract

We investigate how the spectral and topological properties of electron systems evolve on a lattice that interpolates between the honeycomb and its 1/6-depleted structures through the introduction of selective random defects. We find that in certain parameter regimes, the topological properties of the two lattice systems are smoothly connected, whereas in other regimes, selective random defects induce a topological transition. Analysis based on an effective model reveals that the effect of selective random defects can be understood as a modulation of hopping amplitudes. Our results highlight the potential for designing and controlling the spectral and even topological properties of electronic systems across a wide range of material platforms.

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Sogen Ikegami, Kiyu Fukui, Shun Okumura, Yasuyuki Kato, Yukitoshi Motome. 2025-11-18. Topological transition induced by selective random defects on a honeycomb lattice. https://doi.org/10.1103/7n4x-d4nb

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