Non-Abelian topological superconductivity from melting Abelian fractional Chern insulators

Zhengyan Darius Shi; T. Senthil

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arXiv · 2512.17996

Non-Abelian topological superconductivity from melting Abelian fractional Chern insulators

Zhengyan Darius Shi·T. Senthil

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Abstract

Fractional Chern insulators (FCI) are exotic phases of matter realized at partial filling of a Chern band that host fractionally charged anyon excitations. Recent numerical studies in several microscopic models reveal that increasing the bandwidth in an FCI can drive a direct transition into a charge-2e superconductor rather than a conventional Fermi liquid. Motivated by this surprising observation, we propose a theoretical framework that captures the intertwinement between superconductivity and fractionalization in a lattice setting. Leveraging the duality between three field-theoretic descriptions of the Jain topological order, we find that bandwidth tuning can drive a single parent FCI at $\nu = 2/3$ into five different superconductors, some of which are intrinsically non-Abelian and support Majorana zero modes. Our results reveal a rich landscape of exotic superconductors with no normal state Fermi surface and predict novel higher-charge superconductors coexisting with neutral non-Abelian topological order at more general filling fractions $\nu = p/(2p+1)$.

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Zhengyan Darius Shi, T. Senthil. 2025-12-19. Non-Abelian topological superconductivity from melting Abelian fractional Chern insulators. https://arxiv.org/abs/2512.17996

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