论文标题
极性引起的NDNIO2/SRTIO3接口处的电子和原子重建
Polarity induced electronic and atomic reconstruction at NdNiO2/SrTiO3 interfaces
论文作者
论文摘要
最近在SRTIO3上生长的SR掺杂的NDNIO2膜中观察到了超导性。它是由接口引起还是与接口相关的问题仍然是一个空旷的问题。为了解决这个问题,我们使用密度功能理论计算和电荷传递自洽模型来研究NDNIO2/SRTIO3界面上极性不连续性对电子和原子重建的影响。我们发现,与纯电子重建的尖锐界面在能量上是不利的,而原子重建是不可避免的。我们进一步提出了一个可能包含残留顶端氧的接口构型。这些氧原子在费米水平上导致DZ2和DX2-Y2状态的杂种,从而削弱了单带特征,并且可能对超导性有害。
Superconductivity has recently been observed in Sr-doped NdNiO2 films grown on SrTiO3. Whether it is caused by or related to the interface remains an open question. To address this issue, we use density functional theory calculation and charge transfer self-consistent model to study the effects of polar discontinuity on the electronic and atomic reconstruction at the NdNiO2/SrTiO3 interface. We find that sharp interface with pure electronic reconstruction only is energetically unfavorable, and atomic reconstruction is unavoidable. We further propose a possible interface configuration that contain residual apical oxygen. These oxygen atoms lead to hybrids of dz2 and dx2-y2 states at the Fermi level, which weaken the single-band feature and may be detrimental to superconductivity.