Ghimire N J, Ronning F, Williams D J, Scott B L, Luo Yongkang, Thompson J D, Bauer E D
Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
J Phys Condens Matter. 2015 Jan 21;27(2):025601. doi: 10.1088/0953-8984/27/2/025601. Epub 2014 Dec 15.
The synthesis, crystal structure and physical properties studied by means of x-ray diffraction, magnetic, thermal and transport measurements of CeMAl4Si2 (M = Rh, Ir, Pt) are reported, along with the electronic structure calculations for LaMAl4Si2 (M = Rh, Ir, Pt). These materials adopt a tetragonal crystal structure (space group P4/mmm) comprised of BaAl4 blocks, separated by MAl2 units, stacked along the c-axis. Both CeRhAl4Si2 and CeIrAl4Si2 order antiferromagnetically below TN1 = 14 and 16 K, respectively, and undergo a second antiferromagnetic transitition at lower temperature (TN2 = 9 and 14 K, respectively). CePtAl4Si2 orders ferromagnetically below TC = 3 K with an ordered moment of μsat = 0.8 μB for a magnetic field applied perpendicular to the c-axis. Electronic structure calculations reveal quasi-2D character of the Fermi surface.
报道了通过X射线衍射、磁性、热学和输运测量对CeMAl4Si2（M = Rh、Ir、Pt）进行的合成、晶体结构和物理性质研究，以及对LaMAl4Si2（M = Rh、Ir、Pt）的电子结构计算。这些材料采用四方晶体结构（空间群P4/mmm），由BaAl4块组成，由MAl2单元隔开，沿c轴堆叠。CeRhAl4Si2和CeIrAl4Si2分别在TN1 = 14 K和16 K以下呈现反铁磁有序，并在较低温度下经历第二次反铁磁转变（分别为TN2 = 9 K和14 K）。CePtAl4Si2在TC = 3 K以下呈现铁磁有序，对于垂直于c轴施加的磁场，有序磁矩为μsat = 0.8 μB。电子结构计算揭示了费米面的准二维特征。
