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arXiv · 2507.09418

Topological in-gap chiral edge states in superconducting Haldane model with spin-orbit coupling

Sajid Sekh·Andrzej Ptok
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Abstract

Topological superconductivity is currently one of the prime interests, given the properties of its exotic nature of chiral edge states. A broken time-reversal symmetry (TRS) is an essential ingredient in the recipe of a chiral edge state. The Haldane model is one of the many factors that can break TRS in a system. Thus, we explore the possibility of topological superconductivity in the Haldane model under the influence of a conventional superconductor. The edge states originating from such recipes mostly remain outside the superconducting gap. Contrary to this, in the presence of spin-orbit coupling, the edge modes lie within the superconducting gap, and can lead to a gapless state for some range of parameters. Moreover, we use band inversion and projection on the real-space lattice to confirm the topological and chiral nature of the obtained edge states.

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Sajid Sekh, Andrzej Ptok. 2025-07-12. Topological in-gap chiral edge states in superconducting Haldane model with spin-orbit coupling. https://doi.org/10.1103/yq13-3q8p

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