论文标题
三重Perovskite ba $ _ {3} $ coir $ _ {2} $ o $ $ $ _ {9} $的结构，磁性和电子特性的演变
Evolution of the structural, magnetic and electronic properties of the triple perovskite Ba$_{3}$CoIr$_{2}$O$_{9}$
论文作者
论文摘要
我们报告了三重钙钛矿iriate ba $ _ {3} $ coir $ _ {2} $ o $ $ _ {9} $的全面调查。稳定在室温下在室温下的六角形$ p6_ {3}/mmc $对称性，该系统在磁性相变的单斜利$ c2/c $对称性。在进一步降低温度时，系统部分扭曲为较低的对称性（$ p2/c $），这两种结构上不同的相位均共存至最低测量的温度。由中子衍射数据确定的磁结构表明弱倾斜的抗铁磁结构，这也得到了第一原理计算的支持。理论表明，IR $^{5+} $具有有限的磁矩，这也与中子数据一致。这表明避免了推定的$ j = 0 $状态。热容量，电阻噪声和介电敏感性的测量都指向BA $ _ {3} $ coir $ _ {2} $ o $ $ $ _ {9} $系统中高度相关的基态稳定。
We report a comprehensive investigation of the triple perovskite iridate Ba$_{3}$CoIr$_{2}$O$_{9}$. Stabilizing in the hexagonal $P6_{3}/mmc$ symmetry at room temperature, this system transforms to a monoclinic $C2/c$ symmetry at the magnetic phase transition. On further reduction in temperature, the system partially distorts to an even lower symmetry ($P2/c$), with both these structurally disparate phases coexisting down to the lowest measured temperatures. The magnetic structure as determined from neutron diffraction data indicates a weakly canted antiferromagnetic structure, which is also supported by first-principles calculations. Theory indicates that the Ir$^{5+}$ carries a finite magnetic moment, which is also consistent with the neutron data. This suggests that the putative $J=0$ state is avoided. Measurements of heat capacity, electrical resistance noise and dielectric susceptibility all point towards the stabilization of a highly correlated ground state in the Ba$_{3}$CoIr$_{2}$O$_{9}$ system.
