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arXiv · 2505.12342

Enhancement of d-wave Pairing in Strongly Correlated Altermagnet

Jianyu Li·Ji Liu·Xiaosen Yang·Ho-Kin Tang
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Abstract

Altermagnetism, featuring momentum-dependent spin splitting without net magnetization, has attracted a growing interest for spintronics. We study a Fermi Hubbard model with altermagnetic order arising from the spin-anisotropic hopping near half-filling using constrained-path quantum Monte Carlo. Spin-dependent hopping breaks SU(2) symmetry and disrupts Fermi surface nesting, giving rise to an altermagnetic state with momentum-space spin splitting but no net magnetization. We find that increasing anisotropy suppresses long-range antiferromagnetic order and significantly enhances effective $d$-wave pairing correlations. Our results demonstrate a doping-free route to unconventional superconductivity mediated by short-range spin fluctuations in an altermagnetic background.

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Jianyu Li, Ji Liu, Xiaosen Yang, Ho-Kin Tang. 2025-05-18. Enhancement of d-wave Pairing in Strongly Correlated Altermagnet. https://arxiv.org/abs/2505.12342

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