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arXiv · 2506.16464

Antiferromagnetism and Tightly Bound Cooper Pairs Induced by Kinetic Frustration

Yixin Zhang·Cristian Batista·Yang Zhang
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Abstract

Antiferromagnetism and superconductivity are often viewed as competing orders in correlated electron systems. Here, we demonstrate that kinetic frustration in hole motion facilitates their coexistence within the square-lattice repulsive Hubbard model. Combining exact analytical solutions on tailored geometries with large-scale numerical simulations, we reveal a robust pairing mechanism: holes on opposite sublattices behave as if they carry opposite effective charges due to spin singlet formation from kinetic frustration. This emergent property suppresses phase separation and fosters a coherent $d$-wave superconducting channel embedded within a long-range antiferromagnetic background. Our findings establish a minimal yet broadly applicable framework for stabilizing strong-coupling superconductivity in doped Mott insulators.

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Yixin Zhang, Cristian Batista, Yang Zhang. 2025-06-19. Antiferromagnetism and Tightly Bound Cooper Pairs Induced by Kinetic Frustration. https://arxiv.org/abs/2506.16464

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