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arXiv · 2507.01824

Correlation-driven quantum geometry effects in a Kondo system

Abstract

Quantum geometry, including quantum metric and Berry curvature, which describes the topology of electronic states, can induce fascinating physical properties. Symmetry-dependent nonlinear transport has emerged as a sensitive probe of these quantum geometric properties. However, its interplay with strong electronic correlations has rarely been explored in bulk materials, particularly in a Kondo lattice system. Here, we uncover correlation-driven quantum geometry in centrosymmetric antiferromagnetic iron telluride (FeTe). We experimentally observe the quantum metric quadrupole-induced third-order nonlinear transport, whose angular dependence reflects magnetic structure in FeTe. The nonlinear transport signals follow Kondo lattice crossover and vanish at high temperatures. Our theory suggests that a Kondo lattice formed at low temperatures explains the emergence of quantum geometry, which is induced by the opening of a hybridization gap near the Fermi energy. This discovery establishes a paradigm where quantum geometry arises not from static symmetry breaking but from dynamic many-body effects and provides a zero-field probe for sensing antiferromagnetic order.

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Ruizi Liu, Zehan Chen, Xingkai Cheng, Xiaolin Ren, Yiyang Zhang, Xuezhao Wu, Chengping Zhang, Kun Qian, Ching Ho Chan, Junwei Liu, Kam Tuen Law, Qiming Shao. 2025-07-02. Correlation-driven quantum geometry effects in a Kondo system. https://arxiv.org/abs/2507.01824

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