Avoided ferromagnetic quantum critical point in pressurized La${}_5$Co${}_2$Ge${}_3$

Abstract

We present the pressure-temperature phase diagram La${}_5$Co${}_2$Ge${}_3$ up to $\sim$ 5\,GPa, which was constructed from magnetization, resistivity and specific heat measurements. At ambient pressure, La${}_5$Co${}_2$Ge${}_3$ is an itinerant ferromagnet with a Curie temperature $T_{\text{C}}\sim$ 4\,K. Upon increasing pressure up to $\sim$ 1.7\,GPa, $T_{\text{C}}$ is suppressed down to $\sim$ 3\,K. Upon further increasing pressure, our results suggest that La${}_5$Co${}_2$Ge${}_3$ enters a different low-temperature ground state. The corresponding transition temperature, $T^{\ast }$, has a nonmonotonic pressure dependence up to $\sim$ 5\,GPa. Our results demonstrate that the ferromagnetic quantum critical point in La${}_5$Co${}_2$Ge${}_3$ is avoided by the appearance of a different, likely magnetically ordered state that has an antiferromagnetic component.

7 pages, 7 figures

References in corpus (7)

• High-temperature superconductivity in iron-based materials
• Quantum Criticality in Heavy Fermion Metals
• Pressure induced superconductivity on the border of magnetic order in MnP
• Spin-fluctuation dominated electrical transport of Ni3Al at high pressure
• Formation of short-range magnetic order and avoided ferromagnetic quantum criticality in pressurized LaCrGe${}_3$
• Quantum triple point and quantum critical endpoints in metallic magnets
• Use of Cernox thermometers in AC specific heat measurements under pressure