Abstract:

In strongly correlated electron systems, a magnetic transition can be continuously suppressed to zero temperature upon applying a non-thermal parameter like 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]. Over the past years, antiferromagnetic quantum criticality has been widely observed in various correlated systems. However, a ferromagnetic quantum critical point is usually avoided in a clean ferromagnetic system. Recently, we show clear evidence for a pressure-induced ferromagnetic quantum critical point and the associated strange behavior in the stoichiometric heavy fermion metal CeRh6Ge4 [2]. In this seminar, I will present our progresses on the studies of this compound, including the effect of pressure [2] and chemical doping [3], measurements of quantum oscillations [4], ARPES [5] and neutron scattering [6].

References:

[1] Z. F. Weng et al., Rep. Prog. Phys. 79, 094503 (2016).

[2] B. Shen et al., Nature 579, 51 (2020).

[3] Y. J. Zhang et al., unpublished.

[4] A. Wang et al., Science Bulletin 66, 1389 (2021)

[5] Y. Wu et al., PRL 126, 216406 (2021)

[6] J. W. Shu et al., PRB 104, L140411 (2021)