日程 : 2021年8月30日(月) 10:00 - 11:00
場所 : オンライン
講師 : Prof. Huiqiu Yuan
所属 : Center for Correlated Matter and Department of Physics, Zhejiang University
主催 : 強磁場コラボラトリー
世話人 : 小濱 芳充
e-mail : ykohama@issp.u-tokyo.ac.jp
要旨：
In correlated electron systems, a magnetic transition can be continuously suppressed to zero temperature upon applying a non-thermal parameter such as pressure, magnetic field or doping, giving rise to a quantum critical point (QCP), around which unconventional superconductivity and non-Fermi liquid behavior may appear [1]. In this talk, I will briefly present our recent progresses on the studies of magnetic quantum criticality in the d- and f-electron compounds, with focus on the observations of field-induced antiferromagnetic quantum criticality in CdAs1-xPx, and pressure-induced ferromagnetic quantum criticality in CeRh6Ge4. In CdAs1-xPx, the first-order antiferromagnetic order shows highly unusual behavior in a magnetic field. On the other hand, it has been widely believed that a ferromagnetic quantum critical point is avoided in a pure system [2]. Here, I will show you the first compelling evidence for the existence of a pressure-induced ferromagnetic quantum critical point and its associated strange metal behavior in a clean heavy-fermion compound CeRh6Ge4 [3], which shows characteristics of localized magnetism [4] and anisotropic hybridization [5]. If time allows, I will also briefly present the results of CeRhIn5 measured under high pressure or/and high magnetic field [6].
[1] Z. F. Weng et al., Rep. Prog. Phys. 79, 094503 (2016).
[2] M. Brando et al., Rev. Mod. Phys. 88, 025006 (2016) and references therein.
[3] B. Shen et al., Nature 579, 51 (2020).
[4] A. Wang et al., Science Bulletin 66, 1389 (2021)
[5] Y. Wu et al., PRL 126, 216406 (2021)
[6] L. Jiao et al., PRB 99, 045127 (2019); PNAS 112, 673 (2015); A. Wang et al., unpublished.
または
Japanese / English