From Fractionalization to Chiral Topological Superconductivity in a Flat Chern Band

Daniele Guerci; Ahmed Abouelkomsan; Liang Fu

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arXiv · 2506.10938

From Fractionalization to Chiral Topological Superconductivity in a Flat Chern Band

Daniele Guerci·Ahmed Abouelkomsan·Liang Fu

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Abstract

We show that interacting electrons in a flat Chern band can form, in addition to fractional Chern insulators, a chiral $f$-wave topological superconductor that hosts neutral Majorana fermion edge modes. Superconductivity emerges from an interaction-induced metallic state that exhibits anomalous Hall effect, as observed in rhombohedral graphene and near the $\nu=\frac{2}{3}$ fractional Chern insulator in twisted transition metal dichalcogenides.

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Daniele Guerci, Ahmed Abouelkomsan, Liang Fu. 2025-06-12. From Fractionalization to Chiral Topological Superconductivity in a Flat Chern Band. https://arxiv.org/abs/2506.10938

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