Anisotropic magnetic properties of single crystalline RAu_{2}Ge_{2} (R = La, Ce and Pr) compounds are reported. LaAu_{2}Ge_{2} exhibit a Pauli-paramagnetic behavior whereas CeAu_{2}Ge_{2} and PrAu_{2}Ge_{2} show an antiferromagnetic ordering with N\grave{e}el temperatures T_{N} = 13.5 and 9 K, respectively. The anisotropic magnetic response of Ce and Pr compounds establishes [001] as the easy axis of magnetization and a sharp spin-flip type metamagnetic transition is observed in the magnetic isotherms. The resistance and magnetoresistance behavior of these compounds, in particular LaAu_{2}Ge_{2}, indicate an anisotropic Fermi surface. The magnetoresistivity of CeAu_{2}Ge_{2} apparently reveals the presence of a residual Kondo interaction. A crystal electric field analysis of the anisotropic susceptibility in conjunction with the experimentally inferred Schottky heat capacity enables us to propose a crystal electric field level scheme for Ce and Pr compounds. For CeAu_{2}Ge_{2} our values are in excellent agreement with the previous reports on neutron diffraction. The heat capacity data in LaAu_{2}Ge_{2} show clearly the existence of Einstein contribution to the heat capacity.
Giant Magnetocrystalline Anisotropy in Honeycomb Iridate NiIrO3 with Large Coercive Field Exceeding 17 T
School of Chemistry, Sun Yat-Sen University（中山大学化学学院）；School of Chemistry and Environment, Jiaying University（嘉应学院化学与环境学院）；School of Physics, Sun Yat-Sen University（中山大学物理学院）；School of Physics, Huazhong University of Science and Technology（华中科技大学物理学院）；Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）；School of Chemistry and Chemical Engineering, Hainan University（海南大学化学化工学院）
本文采用密度泛函理论（DFT）+U方法对插层硫族化合物材料\ce{Fe_{0.25}TaS_2}的大磁晶各向异性进行了第一性原理研究。我们验证了单轴磁晶各向异性能（MAE）为15 meV/Fe。in the material材料.我们进一步分析了MAE对组成元素的依赖性以及自旋轨道耦合的影响。与传统的直觉相反，我们发现由于较重的元素Ta中的强自旋轨道耦合对MAE的贡献很小。结果表明，磁性离子的电子组态、晶场环境和相关效应是影响磁性离子稳定性的重要因素。
Pressure control of the magnetic anisotropy of the quasi-two-dimensional van der Waals ferromagnet Cr$_2$Ge$_2$Te$_6$
我们报告的静态磁化强度和铁磁共振（FMR）的Cr $_2$ Ge $_2$ Te $_6$的压力相关的测量结果，以解决这个准二维范德华磁体的铁磁相的属性。静磁数据在静水压力高达3.4 GPa揭示了铁磁性的临界转变温度的降低，加宽的过渡宽度和增加的领域完全饱和的磁化$M_{\rm s}$方面的逐渐抑制。$M_{\rm s} \simeq 3μ_{\rm B}$ /Cr的值在高达2.8 GPa的压力下在误差条内保持恒定。FMR信号的各向异性不断减少，在所研究的静水压力范围高达2.39 GPa，这表明易轴型磁晶各向异性能（MAE）的减少。对FMR数据的定量分析证明，在此压力下，MAE常数$K_{\rm U}$虽然明显变小，但仍然是有限的正值，即易轴型。因此，最近讨论的在Cr $_2$ Ge $_2$ Te $_6$中切换磁晶各向异性的符号的可能性只能在更高的压力下预期，如果可能的话，这是由于在压力下观察到的铁磁性的减弱。这种情况可能与包含Cr $_2$ Ge $_2$ Te $_6$层的应变工程功能异质结构的设计有关。
