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arXiv · 2312.12775

Quantum Criticality in YbCu4Ni

Kotaro Osato·Takanori Taniguchi·Hirotaka Okabe·Takafumi Kitazawa·Masahiro Kawamata·Zhao Hongfei·Yoichi Ikeda·Yusuke Nambu·Dita Puspita Sari·Isao Watanabe·Jumpei G Nakamura·Akihiro Koda·Jun Gouchi·Yoshiya Uwatoko·Masaki Fujita
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Abstract

We report on the quantum criticality of YbCu$_4$Ni as revealed by our combined micro- and macro-measurements. We determine the crystal structure of YbCu$_4$Ni with site mixing by neutron diffraction measurements, which suggests the possible presence of Kondo disorder. However, decreasing the local spin susceptibility distribution and the development of spin fluctuations below 10 K at ambient pressure by muon spin rotation and relaxation measurements suggests that YbCu4Ni exhibits quantum criticality. Therefore, our experimental results indicate that YbCu4Ni is a new material that exhibits quantum criticality under a zero magnetic field and ambient pressure.

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Kotaro Osato, Takanori Taniguchi, Hirotaka Okabe, Takafumi Kitazawa, Masahiro Kawamata, Zhao Hongfei, Yoichi Ikeda, Yusuke Nambu, Dita Puspita Sari, Isao Watanabe, Jumpei G Nakamura, Akihiro Koda, Jun Gouchi, Yoshiya Uwatoko, Masaki Fujita. 2023-12-20. Quantum Criticality in YbCu4Ni. https://arxiv.org/abs/2312.12775

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