Jung Myung-Chul, LaBollita Harrison, Pardo Victor, Botana Antia S
Department of Physics, Arizona State University, Tempe, AZ, 85287, USA.
Instituto de Materiais iMATUS, Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain.
Sci Rep. 2022 Oct 25;12(1):17864. doi: 10.1038/s41598-022-22176-2.
We provide a set of computational experiments based on ab initio calculations to elucidate whether a cuprate-like antiferromagnetic insulating state can be present in the phase diagram of the low-valence layered nickelate family (R[Formula: see text]Ni[Formula: see text]O[Formula: see text], R= rare-earth, [Formula: see text]) in proximity to half-filling. It is well established that at [Formula: see text] filling the infinite-layer ([Formula: see text]) nickelate is metallic, in contrast to cuprates wherein an antiferromagnetic insulator is expected. We show that for the Ruddlesden-Popper (RP) reduced phases of the series (finite n) an antiferromagnetic insulating ground state can naturally be obtained instead at [Formula: see text] filling, due to the spacer RO[Formula: see text] fluorite slabs present in their structure that block the c-axis dispersion. In the [Formula: see text] nickelate, the same type of solution can be derived if the off-plane R-Ni coupling is suppressed. We show how this can be achieved if a structural element that cuts off the c-axis dispersion is introduced (i.e. vacuum in a monolayer of RNiO[Formula: see text], or a blocking layer in multilayers formed by (RNiO[Formula: see text])[Formula: see text]/(RNaO[Formula: see text])[Formula: see text]).
我们基于从头算计算提供了一组计算实验，以阐明在低价层状镍酸盐家族（R[化学式：见原文]Ni[化学式：见原文]O[化学式：见原文]，R = 稀土，[化学式：见原文]）接近半填充的相图中是否可以存在类似铜酸盐的反铁磁绝缘态。众所周知，在[化学式：见原文]填充时，无限层（[化学式：见原文]）镍酸盐是金属性的，这与预期为反铁磁绝缘体的铜酸盐形成对比。我们表明，对于该系列的Ruddlesden-Popper（RP）还原相（有限n），由于其结构中存在的间隔层RO[化学式：见原文]萤石板阻断了c轴色散，在[化学式：见原文]填充时反而可以自然地获得反铁磁绝缘基态。在[化学式：见原文]镍酸盐中，如果面外R-Ni耦合被抑制，也可以得到相同类型的解。我们展示了如果引入一个切断c轴色散的结构元素（即RNiO[化学式：见原文]单层中的真空，或由（RNiO[化学式：见原文]）[化学式：见原文]/（RNaO[化学式：见原文]）[化学式：见原文]形成的多层中的阻挡层），如何实现这一点。
