论文标题
无限层中充电顺序的电子起源
An electronic origin of charge order in infinite-layer nickelates
论文作者
论文摘要
带有波形$ \ mathbf {q} \ simeq \ left（\ frac {1} {3} {3}，0,0 \ right）$的充电顺序（CO）在Infinite-Layer镍盐中观察到。在这里，我们使用第一原理计算来证明无限层镍液中的电荷传输驱动的CO机制，从而导致特征性的Ni $^{1+} $ - Ni $ -ni $^{2+} $ -ni $^{1+} $ stripe State。每三个Ni原子，由于存在接近Fermi级的传导带，因此在Ni-$ d $轨道上的Hubbard相互作用将电子传输到一个Ni原子上，以传导带，并在其他两个Ni原子上留下电子，以更具位置。我们进一步得出了一个低能量的有效模型，以阐明CO状态是由Hubbard相互作用在Ni-$ d $轨道上的微妙竞争引起的，而Ni-$ d $ d $轨道和传导带之间的电荷转移能量。使用物理上合理的参数，$ \ mathbf {q} = \ left（\ frac {1} {3} {3}，0,0 \ right）$ co状态比统一的pragagnetic状态和常规的Checkerboard抗Fiferromagnetic状态更稳定。我们的工作突出了无限层镍的多频段性质，这导致了一些独特的相关性能，这些特性在丘比特中未发现。
A charge order (CO) with a wavevector $\mathbf{q}\simeq\left(\frac{1}{3},0,0\right)$ is observed in infinite-layer nickelates. Here we use first-principles calculations to demonstrate a charge-transfer-driven CO mechanism in infinite-layer nickelates, which leads to a characteristic Ni$^{1+}$-Ni$^{2+}$-Ni$^{1+}$ stripe state. For every three Ni atoms, due to the presence of near-Fermi-level conduction bands, Hubbard interaction on Ni-$d$ orbitals transfers electrons on one Ni atom to conduction bands and leaves electrons on the other two Ni atoms to become more localized. We further derive a low-energy effective model to elucidate that the CO state arises from a delicate competition between Hubbard interaction on Ni-$d$ orbitals and charge transfer energy between Ni-$d$ orbitals and conduction bands. With physically reasonable parameters, $\mathbf{q}=\left(\frac{1}{3},0,0\right)$ CO state is more stable than uniform paramagnetic state and usual checkerboard antiferromagnetic state. Our work highlights the multi-band nature of infinite-layer nickelates, which leads to some distinctive correlated properties that are not found in cuprates.
