Field-Induced Criticality in YbCu4Au

T. Taniguchi; K. Osato; H. Okabe; T. Kitazawa; M. Kawamata; S. Hashimoto; Y. Ikeda; Y. Nambu; D. P. Sari; I. Watanabe; J. G. Nakamura; A. Koda; J. Gouchi; Y. Uwatoko; S. Kittaka; T. Sakakibara; M. Mizumaki; N. Kawamura; T. Yamanaka; K. Hiraki; T. Sasaki; M. Fujita

arXiv · 2411.05280

Field-Induced Criticality in YbCu4Au

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Abstract

YbCu4Au is a unique material exhibiting multiple quantum fluctuations simultaneously. In this study, we investigated the field-induced criticality in YbCu4Au, based on comprehensive micro and macro measurements, including powder X-ray diffraction (XRD), neutron powder diffraction (NPD), nuclear magnetic resonance, magnetization, resistivity, specific heat, muon spin rotation relaxation (muSR), and X-ray absorption spectroscopy (XAS). Single crystals of YbCu4Au were grown, and their crystal structure was determined using XRD, and NPD measurements. Magnetic successive transitions were observed below 1 T by specific heat, resistivity, NPD, and muSR measurements. XAS measurements further indicate that the valence of Yb ions (+2.93) remained unchanged above 2 T. Moreover, the change in quadrupole frequency observed in the previous study is attributable to the electric quadrupole, as the expected value of the electric quadrupole was finite under magnetic fields [S. Wada et al., Journal of Physics: Condensed Matter, 20, 175201 (2008).]. These experimental results suggest that YbCu4Au exhibited bicritical behavior near 1 T, arising from the competition between RKKY interaction, accounting for the magnetic phases, and the Zeeman effect.

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T. Taniguchi, K. Osato, H. Okabe, T. Kitazawa, M. Kawamata, S. Hashimoto, Y. Ikeda, Y. Nambu, D. P. Sari, I. Watanabe, J. G. Nakamura, A. Koda, J. Gouchi, Y. Uwatoko, S. Kittaka, T. Sakakibara, M. Mizumaki, N. Kawamura, T. Yamanaka, K. Hiraki, T. Sasaki, M. Fujita. 2024-11-08. Field-Induced Criticality in YbCu4Au. https://arxiv.org/abs/2411.05280

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