具有电子与晶格不稳定性的反铁磁金属GdB₆的三维（H-theta-phi）磁相图
3D- (H-theta-phi) magnetic phase diagram of antiferromagnetic metal GdB6 with electron and lattice instability
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中文总结 AI 辅助
本研究探究反铁磁金属GdB₆的电荷输运与磁化各向异性起源，发现其存在姜-泰勒畸变与动态电荷条纹，构建磁相图并揭示相关磁结构与交换机制。
中文摘要 AI 辅助
本研究针对具有立方晶格与Gd S型磁性离子的反铁磁（AF）金属GdB₆（奈尔温度T_N≈15.5 K），探究其电荷输运与磁化各向异性的起源。通过高精度低温X射线衍射测量，发现其存在小的静态姜-泰勒畸变与纳米级电子不稳定性（动态电荷条纹）。构建了详细的磁场（H）-温度（T）相图，包含AF(I)与AF(II)两个主要磁相。利用磁阻与磁化的角phi依赖关系，在氦温度下于（110）和（111）面发现H-phi磁相图的叶轮型图案，其中AF(I)与AF(II)相通过径向和圆形边界分隔。结果支持自旋密度波5d分量在AF(II)态磁结构中发挥重要作用；提出条纹中的电荷涨落可抑制沿<100>和<110>方向排列的第一与第二近邻Gd³⁺离子间的Ruderman-Kittel-Kasuya-Yoshida（RKKY）间接交换。这些动态电荷条纹与振动耦合的Gd-Gd对，导致了含S型磁性离子的GdB₆中电荷散射的异常各向异性及叶轮型相图。
英文摘要
The origin of charge transport and magnetization anisotropy was studied in GdB6, an antiferromagnetic (AF) metal (Néel temperature TN ~ 15.5 K) with cubic lattice and Gd S-type magnetic ions. Both small static Jahn-Teller distortions and nanoscale electronic instabilities (dynamic charge stripes) were found in precise low temperature X-ray diffraction measurements. The detailed magnetic field (H) vs temperature (T) phase diagrams were constructed with two main magnetic phases AF(I) and AF(II). Using the angular phi-dependences of magnetoresistance and magnetization, impeller-type patterns of the H-phi magnetic phase diagrams in the (110) and (111) planes were found at helium temperatures, which included the AF phases I and II separated from each other by radial and circular boundaries. The results argue in favor of the important role of the spin density wave 5d- component in the magnetic structure of AF(II) state. Charge fluctuations in stripes are proposed to be responsible for the suppression of the Ruderman-Kittel-Kasuya-Yoshida (RKKY) indirect exchange between the first and second neighboring Gd3+ ions located along the <100> and <110> directions. These dynamic charge stripes and vibrationally coupled Gd-Gd pairs produce unusual anisotropy of charge scattering and the impeller-type diagrams in GdB6 with S-type magnetic ion.
