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arXiv · 2510.10684

Integrable Model of a Superconductor with non-Fermi liquid and Mott Phases

Santhosh M·Jorge Dukelsky·Gerardo Ortiz
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Abstract

We present and analyze an exactly solvable interacting fermionic pairing model, which features interactions that entangle states at momenta $\mathbf{k}$ and $-\mathbf{k}$. These interactions give rise to novel correlated ground states, leading to a rich phase diagram that includes superconducting, multiple metallic, and Mott-insulating phases. At finite interaction strengths, we observe the emergence of multiple many-body Fermi surfaces, which violate Luttinger's theorem and challenge the conventional Landau-Fermi liquid paradigm. A distinguishing feature of our model is that it remains quantum integrable, even with the addition of pairing interactions of various symmetries, setting it apart from the Hatsugai-Kohmoto model. Our results provide an analytically tractable framework for studying strong correlation effects that give rise to fractionalized excitations and unconventional superconductivity, offering valuable insights into a broad class of integrable many-body systems.

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Santhosh M, Jorge Dukelsky, Gerardo Ortiz. 2025-10-12. Integrable Model of a Superconductor with non-Fermi liquid and Mott Phases. https://doi.org/10.1103/h7fk-2n35

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