Antiferromagnetic Kondo lattice in the layered compound CePd 1 -x Bi 2 and comparison to the superconductor LaPd 1 -x Bi 2
Antiferromagnetic Kondo lattice in the layered compound CePd 1 -x Bi 2 and comparison to the superconductor LaPd 1 -x Bi 2
复制标题
层状化合物 CePd 1 -x Bi 2 中的反铁磁 Kondo 晶格及其与超导体 LaPd 1 -x Bi 2 的比较
DOI：
10.1103/physrevb.92.045112
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
M. Kanatzidis
中科院分区：
文献类型：
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作者：
Fei Han;X. Wan;D. Phelan;C. Stoumpos;Mihai I. Sturza;C. Malliakas;Qing’an Li;T. Han;Qingbiao Zhao;D. Chung;M. Kanatzidis
采用过量Bi助熔剂制备了具有四方ZrCuSi结构的层状化合物CePd_（1-x）Bi_（10）。CePd_（1-x）Bi_（1-x）的磁化率数据显示，在低于6 K时，样品具有反铁磁有序性，并且沿c轴和ab平面沿着具有各向异性.将这种各向异性归因于晶体电场效应，并给出了一个能够描述磁化率数据的晶体电场模型。由比热测量得到的增强索末菲系数γ为0.191 J mol CePd 1-xBi_xO_2，表明CePd 1-xBi_xO_xO_2中存在适度的近藤效应。除了6 K处的反铁磁峰外，电阻率曲线在75 K附近表现出肩状行为，这可能归因于近藤效应和CEF效应之间的相互作用。磁电阻和霍尔效应的测量表明，相互作用重建的费米表面拓扑结构的CePd 1-xBi双金属氧化物在75 K左右。电子结构计算表明，Pd空位是重要的磁结构和增强的CEF效应，淬灭的Ce的轨道力矩在低温下。
The layered compound CePd1–xBi₂ with the tetragonal ZrCuSi₂-type structure was obtained from excess Bi flux. Magnetic susceptibility data of CePd1–xBi₂ show an antiferromagnetic ordering below 6 K and are anisotropic along the c axis and the ab plane. The anisotropy is attributed to crystal-electric-field (CEF) effects and a CEF model which is able to describe the susceptibility data is given. An enhanced Sommerfeld coefficient γ of 0.191 J mol Ce⁻¹ K⁻² obtained from specific-heat measurement suggests a moderate Kondo effect in CePd1–xBi₂. Other than the antiferromagnetic peak at 6 K, the resistivity curve shows a shoulderlike behavior around 75 K which could be attributed to the interplay between Kondo and CEF effects. Magnetoresistance and Hall-effect measurements suggest that the interplay reconstructs the Fermi-surface topology of CePd1–xBi₂ around 75 K. Electronic structure calculations reveal that the Pd vacancies are important to the magnetic structure and enhance the CEF effects which quench the orbital moment of Ce at low temperatures.