Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China.
Phys Chem Chem Phys. 2018 Oct 3;20(38):24768-24774. doi: 10.1039/c8cp04336a.
The electronic properties of SrRuO3/BiIrO3 superlattices are investigated by first-principles calculations with spin-orbit coupling. The results show that the strength of hybridization near the Fermi level is dependent on the distance between the closest transition metal Ru and Ir atoms. We find that both spin and valley polarizations in bilayered BiIrO3 are achieved in Bi-terminated models. Furthermore, different stacking patterns can modulate the magnitude and sign of valley polarization and switch the p- or n-type doping of bilayered BiIrO3. Meanwhile, a spin-down polarized valley polarization of 79.5 meV can be induced in bilayered SrRuO3. The different thicknesses calculated demonstrate that the valley in the SrRuO3/BiIrO3 model is limited to the bilayered structure. The tunable valley and spin polarizations in SrRuO3/BiIrO3 superlattices would enrich the diversity and boost the development of high-performance spintronic and valleytronic devices.
通过考虑自旋轨道耦合的第一性原理计算，研究了 SrRuO3/BiIrO3 超晶格的电子性质。结果表明，费米能级附近的杂化强度取决于最近的过渡金属 Ru 和 Ir 原子之间的距离。我们发现，在 Bi 终止模型中，双层 BiIrO3 中均实现了自旋和谷极化。此外，不同的堆叠模式可以调节谷极化的大小和符号，并切换双层 BiIrO3 的 p 型或 n 型掺杂。同时，在双层 SrRuO3 中可以诱导出 79.5 meV 的自旋向下极化谷极化。计算出的不同厚度表明，SrRuO3/BiIrO3 模型中的谷局限于双层结构。SrRuO3/BiIrO3 超晶格中可调谐的谷和自旋极化将丰富多样性并推动高性能自旋电子学和谷电子学器件的发展。
