AI 中文总结
研究反铁磁双层Janus YIBr结构，通过第一性原理计算和低能模型，发现不同堆叠下易轴方向不同，价带有狄拉克色散关系，存在自旋、谷和层耦合，外部电场可控制费米能级附近空穴，为探索新特性等提供帮助。
AI 中文摘要
反铁磁二维半导体的改性和增强对于实现新型电子特性及推动有前景的应用至关重要。为此，我们通过第一性原理计算和有效低能模型研究了六种具有不同堆叠变化的反铁磁二维双层Janus YIBr结构。磁各向异性能计算表明易轴方向随堆叠不同而变化。第一性原理计算的能带显示价带中至少在0.3 eV的宽能窗内存在狄拉克相对论色散关系。对自旋、原子性质和贝里曲率的计算表明双层Janus结构中存在自旋、谷和层耦合，有自旋分裂、谷极化，可实现量子谷霍尔绝缘体。进一步分析外部电场的影响可用于控制费米能级附近空穴的自旋、谷和层。这对未来探索双层Janus结构的新特性、控制方法及更多功能有用。
英文摘要
The modification and enhancement of antiferromagnetic two-dimensional semiconductor is considered crucial for realizing novel electronic properties and facilitating promising applications. For this purpose, we investigate six antiferromagnetic 2D bilayer Janus YIBr structures with different stacking variations by means of first-principles calculation and an effective low-energy model. The calculation of magnetic anisotropy energy shows that the direction of easy axis varies with different stacking. First-principles-calculated energy bands reveal that there is a Dirac relativistic dispersion relation exists in the valence band in a wide energy window of 0.3 eV at least. The calculations for spin, atom properties and Berry curvature description show that there is spin, valley and layer coupling with spin splitting, valley polarization and valley Hall and layer Hall effects can be achieved in the bilayer Janus structures. Further analyses of the effect of external electric field can be used to control spin, valley and layer of the hole near the Fermi level and to realize an anomalous valley Hall effect. These can be useful in future exploration for novel properties, control methods and more functionalities in bilayer Janus structures.
Comments8 pages, 6 figures
