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arXiv · 2609.21825

Topological properties and gap structure of the paired state in twisted TMD bilayers within a two-band effective model

Palash Saha·Michał Zegrodnik
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Abstract

We present a theoretical study motivated by the recent experimental results which demonstrate superconductivity emerging from flat topological bands of twisted transition metal dichalcogenide (TMD) bilayers. To capture the non-trivial band topology of the system, we employ an effective two-band Kane-Mele-like model and substitute it with Coulomb repulsion and inter-site pairing interactions treated at the Hartree-Fock mean-field level. Assuming a real-space pairing scenario, we analyze the resulting superconducting gap symmetry and the stability of the paired state as a function of band filling and applied displacement field. Finally, we highlight the interplay between superconductivity and non-trivial topology, detailing how interaction-induced effects and the evolution of the density of states shape the resulting superconducting phase diagram.

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Palash Saha, Michał Zegrodnik. 2026-09-18. Topological properties and gap structure of the paired state in twisted TMD bilayers within a two-band effective model. https://arxiv.org/abs/2609.21825

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