Mechanism of Basal-Plane Antiferromagnetism in the Spin-Orbit Driven Iridate Ba2IrO4
Mechanism of Basal-Plane Antiferromagnetism in the Spin-Orbit Driven Iridate Ba2IrO4
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DOI：
10.1103/physrevx.4.021051
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发表时间：
2014-06-17
影响因子：
12.5
通讯作者：
Rousochatzakis, Ioannis
中科院分区：
文献类型：
--
作者：
Katukuri, Vamshi M.;Yushankhai, Viktor;Rousochatzakis, Ioannis
通过从头算多体量子化学计算，我们确定了5d（5）j近似1/2层状材料Ba 2 IrO 4中对称各向异性的强度.虽然计算出的各向异性耦合在几个meV的范围内，比类似的3d过渡金属化合物强几个数量级，海森堡超交换仍然定义了最大的能量尺度。从头计算结果表明，Ba 2 IrO 4的各个层提供了一个紧密的实现量子自旋1/2海森堡指南针模型上的正方形晶格。我们表明，实验观察到的基面反铁磁性可以占包括额外的层间相互作用和相关的有序无序量子力学效应，在类似于未掺杂的层状铜酸盐。
By ab initio many-body quantum chemistry calculations, we determine the strength of the symmetric anisotropy in the 5d(5) j approximate to 1/2 layered material Ba2IrO4. While the calculated anisotropic couplings come out in the range of a few meV, orders of magnitude stronger than in analogous 3d transition-metal compounds, the Heisenberg superexchange still defines the largest energy scale. The ab initio results reveal that individual layers of Ba2IrO4 provide a close realization of the quantum spin-1/2 Heisenberg-compass model on the square lattice. We show that the experimentally observed basal-plane antiferromagnetism can be accounted for by including additional interlayer interactions and the associated order-by-disorder quantum-mechanical effects, in analogy to undoped layered cuprates.