Antiferro-Quadrupolar Ordering at the Lowest Temperature and Anisotropic Magnetic Field-Temperature Phase Diagram in the Cage Compound PrIr_2Zn_<20>
Antiferro-Quadrupolar Ordering at the Lowest Temperature and Anisotropic Magnetic Field-Temperature Phase Diagram in the Cage Compound PrIr_2Zn_<20>
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笼状化合物PrIr_2Zn_<20>最低温度下的反铁四极有序性及各向异性磁场-温度相图
DOI：
10.1143/jpsj.80.093601
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Takashi Suzuki
中科院分区：
文献类型：
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作者：
Isao Ishii;Hitoshi Muneshige;Yasuhiko Suetomi;Takahiro K.Fujita;Takahiro Onimaru;Keisuke T.Matsumoto;Toshiro Takabatake;Koji Araki;Mitsuhiro Akatsu;Yuichi Nemoto;Terutaka Goto;Takashi Suzuki
具有非Kramers双峰基态的笼状化合物PrIr2Zn20在TQ∼0.11 K处表现出相变。为了研究相变的起源，我们对单晶样品进行了超声测量。从 TQ 处电四极自由度的消失和四极-四极耦合常数的负号，我们澄清了相变在有史以来测量的最低温度下是反铁四极有序的。我们还从平行于 [100]、[110] 和 [111] 轴的 H 测量中发现了各向异性磁场 H 依赖性和 TQ(H) 的重入行为。四极近藤效应会在极低温度下中断长程四极相互作用，从而降低 TQ。我们首先报道了 RT2Zn20 系统中 16c 位点 Zn 原子的震颤运动。
The cage compound PrIr2Zn20with the non-Kramers doublet ground state shows a phase transition atTQ∼0.11 K. To investigate the origin of the phase transition, we have carried out ultrasonic measurements on single-crystalline samples. From the disappearance of electric quadrupole degrees of freedom atTQand the negative sign of a quadrupole–quadrupole coupling constant, we clarified that the phase transition is antiferro-quadrupolar ordering at the lowest temperature ever measured. We also found anisotropic magnetic fieldHdependence and the re-entrant behavior ofTQ(H) from the measurements inHparallel to the [100], [110], and [111] axes. The quadrupole Kondo effect interrupts the long-range quadrupole interaction at very low temperatures and thus lowersTQ. We first reported the rattling motion of Zn atoms at the 16csite in theRT2Zn20system.