论文标题
避免使用加压的铁磁量子关键点$ _5 $ _2 $ _2 $ ge $ _3 $
Avoided ferromagnetic quantum critical point in pressurized La$_5$Co$_2$Ge$_3$
论文作者
论文摘要
我们介绍了压力温度相图LA $ _5 $ co $ _2 $ ge $ _3 $最高$ \ sim $ 5 \ $ 5 \，GPA，该$ 5 \ gpa是由磁化，电阻率和特定的热量测量所构建的。在环境压力下，la $ _5 $ co $ _2 $ ge $ _3 $是带有居里温度的流动型铁磁铁$ t_ \ textrm c \ sim $ 4 \，k。在增加压力后，最高$ \ sim $ 1.7 \，gpa，$ t_ \ textrm c $被抑制至$ \ sim $ 3 \，k。在进一步增加压力的情况下，我们的结果表明la $ _5 $ co $ _2 $ ge $ _3 $进入不同的低温地面状态。相应的过渡温度$ t^*$的非单调压力依赖性高达$ \ sim $ 5 \，GPA。我们的结果表明，LA $ _5 $ co $ _2 $ ge $ _3 $中的铁磁量子关键点可以通过具有抗铁磁成分的不同，可能有磁有序状态的外观来避免。
We present the pressure-temperature phase diagram La$_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 $T_\textrm C\sim$ 4\,K. Upon increasing pressure up to $\sim$ 1.7\,GPa, $T_\textrm C$ 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, $T^*$, 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.
