Quantum-geometry-driven exact ferromagnetic ground state in a nearly flat band

arXiv:2603.01922 · cond-mat.str-el · Submitted 2026-03-02 · Read on arXiv

cond-mat.str-el

Submitted: 2026-03-02

Updated: 2026-08-07

Terminology

• Hubbard Model — 19× in this paper · explained in 3 episodes
• Effective Hamiltonian — 9× in this paper · explained in 2 episodes
• Antiferromagnetism — 3× in this paper · explained in 1 episode
• Degeneracy — 3× in this paper · explained in 3 episodes
• Phase Transitions — 2× in this paper · explained in 2 episodes
• Vector Representations — 1× in this paper · explained in 2 episodes

Sources

• Quantum geometry in correlated electron phases: from flat band to dispersive band
• Quantum geometry in superfluidity and superconductivity
• Anomalous Temperature Dependence of Quantum-Geometric Superfluid Weight
• Quantum geometric bound for saturated ferromagnetism
• Identifying Instabilities with Quantum Geometry in Flat Band Systems
• Quantum geometric ferromagnetism by singular saddle point
• False Vacuum Decay in Flat-Band Ferromagnets: Role of Quantum Geometry and Chiral Edge States
• Roton Superconductivity from Loop-Current Chern Metal on the Kagome Lattice
• Odd-parity magnetism by quantum geometry
• Ferromagnetism vs. Antiferromagnetism in Narrow-Band Systems: Competition Between Quantum Geometry and Band Dispersion
• Magnetic phase transitions driven by quantum geometry
• Magnetic phase transitions protected by topological quantum geometry transitions: effects of electron-electron interactions in the Creutz ladder system
• Quantum geometric magnetic monopole and two-phase superconductivity in CeRh$_2$As$_2$
• Magnetic fluctuations driven by quantum geometry
• Many-Body Superconductivity in Topological Flat Bands
• Exact models of chiral flat-band superconductors
• Quantum-geometry-driven Mott transitions and magnetism

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• Instabilities in self-consistent diagrammatic approaches and how to cure them
• True vs false Fermi surfaces in the Pseudogap regime and their transformation with doping and temperature in the Hubbard Model
• Orbital magnetic susceptibility and de Haas-van Alphen effect of a flat band from quantum geometry