Pressure and magnetic field induced quantum criticality in Yb-based heavy fermion compounds

近年来，位于或接近量子临界点（QCP）的重费米子金属的基态性质是最有趣的话题之一。为了获得基于镱的重费米子系统在压力和磁场作用下的量子临界行为的新见解，我们开发了一种新型高压电池。结合压力和磁场调谐比热测量，揭示了YbCo_2Zn_<20 bbb_的一种新的相图。我们还发现了YbNi_3Ga_9的压力诱导铁磁有序。

In recent years, one of the most interesting topics is the ground state properties of heavy fermion metals located at or close to a quantum critical point(QCP). To obtain the new insights on the quantum critical behavior in Yb-based heavy fermion systems under pressure and magnetic field, we have developed new type of high pressure cell. Combined pressure-and magnetic-field-tuned specific heat measurements reveal a novel phase diagram in YbCo_2Zn_<20>. We also found the pressure-induced ferromagnetic order in YbNi_3Ga_9.