High-pressure synthesis and anomalous properties of new skutterudite-type compounds including heavy lanthanide

重稀土等新型方钴矿型化合物的高压合成及其异常性质

基本信息

批准号：
14204032
负责人：
SHIROTANI Ichimin
金额：
$ 31.03万
依托单位：
Muroran Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

项目摘要

Filled skutterudite compounds LnT_4X_<12> (Ln=Lanthanide ; T=Fe,Ru,Os ; X=P,As,Sb) with space group Im-3 (T^5_h, #204) have attracted much attention because of wide variety of physical properties at low temperature, such as metal-insulator transition, multipole order, heavy-fermion behavior, non Fermi liquid behavior and exotic superconductivity. This remarkable feature is caused by a strong p-f hybridization effect, a unique band structure and an orbital degree of freedam due to f electron in Ln site with cubic symmetry.We have prepared many skutterudites with lighter lanthanide at high temperatures and high pressures. However, few filled skutterudites with heavy lanthanide have been synthesized. We have succeeded to prepare for the first time new filled skutterudites with heavy lanthanide, LnT_4P_<12> (Ln=heavy lanthanide, including Y ; T=Fe,Ru,Os) by the high-pressure technique. New filled skutterudites LnFe_4P_<12> (Ln=Tb,Dy,Ho,Er,Tm,Yb,Lu and Y) were prepared and studied. LnFe_4P_<12> (Ln=Gd,Tb,Dy,Ho,Er) are ferromagnets. YFe_4P_<12> and LuFe_4P_<12> are superconductors. Tm, Yb compounds are paramagnetic down to low temperature. For Ru system, LfRu_4P_<12> (Ln=Gd,Tb,Y) were prepared under high pressure. GdRu_4P_<12> and TbRu_4P_<12> are antiferromagnets. YRu_4P_<12> is a new superconductor (transition temperature Tc=9K). For Os system, new filled skutterudites LnOs_4P_<12> (Ln=Sm,Eu,Gd,Tb,Dy,Ho and Y) were prepared and studied. LnOs_4P_<12> (Ln=Eu,Gd,Tb) are ferromagnets. SmOs_4P_<12> is an antiferromagnet. Dy, Ho compounds are paramagnetic down to low temperature. YOs_4P_<12> is a new superconductor.In this work, we found 16 new filled skuterudites and 4 new superconductors with skutterudite-type structure.

空间群为 Im-3 (T^5_h, #204) 的填充方钴矿化合物 LnT_4X_<12> (Ln=镧系元素 ; T=Fe,Ru,Os ; X=P,As,Sb) 由于种类繁多而备受关注低温物理性质，如金属-绝缘体转变、多极序、重费米行为、非费米液体行为和奇异超导。这一显着特征是由立方对称的Ln位上的f电子产生的强烈的p-f杂化效应、独特的能带结构和轨道自由度造成的。我们在高温高压下制备了许多较轻的镧系元素方钴矿。然而，很少有重稀土元素填充方钴矿被合成。我们首次采用高压技术成功制备了新型重稀土填充方钴矿LnT_4P_<12>（Ln=重稀土，含Y；T=Fe,Ru,Os）。制备并研究了新型填充方钴矿LnFe_4P_<12>(Ln=Tb、Dy、Ho、Er、Tm、Yb、Lu和Y)。 LnFe_4P_<12> (Ln=Gd、Tb、Dy、Ho、Er) 是铁磁体。 YFe_4P_<12>和LuFe_4P_<12>是超导体。 Tm、Yb 化合物在低温下仍具有顺磁性。对于Ru体系，在高压下制备LfRu_4P_ 12 (Ln＝Gd，Tb，Y)。 GdRu_4P_<12>和TbRu_4P_<12>是反铁磁体。 YRu_4P_<12>是一种新型超导体（转变温度Tc=9K）。针对Os体系，制备并研究了新型填充方钴矿LnOs_4P_<12>（Ln=Sm、Eu、Gd、Tb、Dy、Ho和Y）。 LnOs_4P_<12> (Ln=Eu,Gd,Tb) 是铁磁体。 SmOs_4P_<12> 是一种反铁磁体。 Dy、Ho 化合物在低温下仍具有顺磁性。 YOs_4P_<12>是一种新型超导体。在这项工作中，我们发现了16种新型填充方钴矿和4种新型方钴矿型结构超导体。