Exploring metamagnetism of single crystalline \eun\ by neutron scattering

EuNiGe3，等矩各向异性反铁磁体

EuNiGe3, an equal moment anisotropic antiferromagnet

单晶EuNiGe $_3$结晶在非中心对称BaNiSn $_3$型结构已使用In熔剂生长，使我们能够探索各向异性的磁性能，这是不可能与以前报道的多晶样品。EuNiGe $_3$单晶样品的磁化率、热容和电阻率数据表明，样品在13.2 K时具有反铁磁有序性.对于平行于${ab}$平面和$c$轴的磁场，低温磁化强度M（H）明显不同;在6.2 T下出现感应铁磁相（自旋翻转）之前，${ab}$平面磁化强度几乎随磁场线性变化;另一方面，沿$c$轴的M（H）伴随着两次变磁跃迁，随后是4.1 T下的自旋翻转。包括各向异性交换和偶极-偶极相互作用的模型再现了磁化图的主要特征，但没有完全代表性。（H，T）相图已被构造为沿主方向施加的场。从$^{151}$ Eu穆斯堡尔谱，我们确定，13.2 K的过渡导致一个不相称的反铁磁中间相，然后由一个过渡附近10.5 K到一个相称的反铁磁配置。

Epitaxial strain modulated electronic properties of interface controlled nickelate superlattice

Perovskite nickelate heterostructure consisting of single unit cell of EuNiO$_3$ and LaNiO$_3$ have been grown on a set of single crystalline substrates by pulsed laser interval deposition to investigate the effect of epitaxial strain on electronic and magnetic properties at the extreme interface limit. Despite the variation of substrate in-plane lattice constants and lattice symmetry, the structural response to heterostructuring is primarily controlled by the presence of EuNiO$_3$ layer. In sharp contrast to bulk LaNiO$_3$ or EuNiO$_3$, the superlattices grown under tensile strains exhibit me…

Observation of Fermi liquid phase with broken symmetry in a single crystalline nanorod of Pr$_2$Ir$_2$O$_7$

We report experimental evidence of emergent broken symmetry Fermi liquid state in an isolated single crystalline nanorod of $\rm Pr_2 Ir_2 O_7$. We find clear signature of the onset of the Fermi liquid behavior at low temperature marked by the sign inversion of magnetoresistance from negative at high temperature, characteristic of incoherent Kondo scattering, to positive as well as a $\rm T^2$ dependence of resistivity at low temperature. A resistive anomaly is observed, which is accompanied by thermal hysteresis in the presence of magnetic field, suggesting itinerant metamagnetism. The observ…

四元体系YbRu_{2} Ge_{2}的诱导四极序理论

Theory of induced quadrupolar order in tetragonal YbRu_{2}Ge_{2}

四元化合物YbRu $_{2}$ Ge $_{2}$在零磁场下，在$T_0$ =10.2K处发生非磁性转变，在$T_1$ =6.5K处发生磁性转变.我们提出了一种基于准四重态Yb $^{3+}$晶体电场（CEF）的材料模型，并讨论了它的平均场解。考虑到磁场垂直于[001]时$T_0$处比热跃变的加宽和磁场平行于[001]时$T_0$处比热跃变的减小，结果表明O型$_{2}^{2}$或O型$_{\rm xy}$的铁四极阶是非磁跃迁的主要候选者.考虑到这些四极矩的矩阵元，我们证明了该能级方案的低CEF态由一个$Γ_{6}$和一个$Γ_{7}$双重态组成。这导致诱导型O $_{2}^{2}$和O $_{\rm xy}$四极序参数。四极序引入平面磁矩的交换各向异性。这导致在低场垂直[001]下的自旋翻转跃迁，这解释了观察到的变磁性。我们也得到了一个很好的解释的磁化率和比热的温度依赖性的领域都平行和垂直于[001]方向。