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arXiv · 2608.26534

Competition between Geometrical Frustration and the Kondo Effect in CePdAl Revealed by High-Resolution Magnetization

Yusei Shimizu·Shota Nakamura·Yoichi Ikeda·Yohei Kono·Shunichiro Kittaka·Toshiro Sakakibara·Yosikazu Isikawa
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Abstract

CePdAl is a heavy-fermion compound with a quasi-kagome structure, where geometrical frustration competes with the Kondo effect. Using a high-sensitivity magnetometer, we observe clear first-order metamagnetic transitions without magnetization plateaus in CePdAl at 80 mK, indicating a lifting of frustration through the suppression of the Kondo effect and spin flips of ordered moments under fields. An anomaly in the nonlinear magnetic susceptibility at 4.3 T suggests nondipolar correlations in the polarized paramagnetic state. Furthermore, we found no evidence of non-Fermi-liquid behavior in the high-field region, where the antiferromagnetic order is completely suppressed. These findings establish the essential thermodynamic constraints for understanding the field-induced spin-liquid state in CePdAl.

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Yusei Shimizu, Shota Nakamura, Yoichi Ikeda, Yohei Kono, Shunichiro Kittaka, Toshiro Sakakibara, Yosikazu Isikawa. 2026-08-27. Competition between Geometrical Frustration and the Kondo Effect in CePdAl Revealed by High-Resolution Magnetization. https://arxiv.org/abs/2608.26534

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