Department of Physics, National Sun Yat-sen University, Kaohsiung 804, Taiwan.
Phys Rev Lett. 2012 Dec 14;109(24):246807. doi: 10.1103/PhysRevLett.109.246807. Epub 2012 Dec 12.
In this study, direct observation of the evolution of electronic structures across complex oxide interfaces has been revealed in the LaAlO(3)/SrTiO(3) model system using cross-sectional scanning tunneling microscopy and spectroscopy. The conduction and valence band structures across the LaAlO(3)/SrTiO(3) interface are spatially resolved at the atomic level by measuring the local density of states. This study directly maps out the electronic reconstructions and a built-in electric field in the polar LaAlO(3) layer. Results also clearly reveal the band bending and the notched band structure in the SrTiO(3) adjacent to the interface.
在这项研究中，通过使用横截面扫描隧道显微镜和光谱学，在 LaAlO(3)/SrTiO(3) 模型系统中直接观察到了复杂氧化物界面处电子结构的演变。通过测量局部态密度，在原子水平上对 LaAlO(3)/SrTiO(3) 界面处的导带和价带结构进行了空间分辨。这项研究直接绘制出了在极性 LaAlO(3) 层中的电子重构和内置电场。结果还清楚地揭示了界面附近 SrTiO(3)中的能带弯曲和带隙结构。
