论文标题
Cuprate-Analog $ d^9 $镍的磁性交换耦合
Magnetic exchange coupling in cuprate-analog $d^9$ nickelates
论文作者
论文摘要
由于最近在掺杂的ndnio $ _2 $中发现超导性的动机，我们研究了磁性交换交互$ j $ in Laseered $ d^9 $ nickelates，the $ d^9 $ nickelates是从第一原则中的。高$ t _ {\ rm c} $ cuprates的母亲化合物属于Zaanen-Sawatzky-Allen图中的电荷转移制度，并且具有大于100 MEV的$ J $。虽然此功能使碎屑与其他过渡金属氧化物大不相同，但分层$ d^9 $镍也可以拥有如此大的$ j $，这引起了极大的兴趣。但是，一个复杂性是NDNIO $ _2 $不是由于从块层掺杂的载体掺杂而不是mott绝缘子。要在平等的基础上比较库酸盐和$ d^9 $镍盐，我们研究rbca $ _2 $ nio $ _3 $和$ a_ {2} $ nio $ _ {2} $ _ {2} $ br $ _2 $（$ a $：阳离子，阳离子，价值为2.5+$ $ 2.5+$），最近是由Block-Lockessy blove blove blove block-like bake block-leesthe blove block-leesthe block-layeret elemerering。这些镍含量没有自兴奋剂的效果，属于莫特 - 哈伯政权。我们表明，这些镍含量与高$ t _ {\ rm c} $ cuprates共享一个共同的线程，因为它们还具有大约100 meV的大量交换交互$ j $。
Motivated by the recent discovery of superconductivity in doped NdNiO$_2$, we study the magnetic exchange interaction $J$ in layered $d^9$ nickelates from first principles. The mother compounds of the high-$T_{\rm c}$ cuprates belong to the charge-transfer regime in the Zaanen-Sawatzky-Allen diagram and have $J$ larger than 100 meV. While this feature makes the cuprates very different from other transition metal oxides, it is of great interest whether layered $d^9$ nickelates can also have such a large $J$. However, one complexity is that NdNiO$_2$ is not a Mott insulator due to carrier doping from the block layer. To compare the cuprates and $d^9$ nickelates on an equal basis, we study RbCa$_2$NiO$_3$ and $A_{2}$NiO$_{2}$Br$_2$ ($A$: a cation with the valence of $2.5+$), which were recently designed theoretically by block-layer engineering. These nickelates are free from the self-doping effect and belong to the Mott-Hubbard regime. We show that these nickelates share a common thread with the high-$T_{\rm c}$ cuprates in that they also have a significant exchange interaction $J$ as large as about 100 meV.
