Despite several attempts, the intimate electronic structure of two-dimensional electron systems buried at the interface between LaAlO₃ and SrTiO₃ still remains to be experimentally revealed. Here, we investigate the transport properties of a high-mobility quasi-two-dimensional electron gas at this interface under high magnetic field (55 T) and provide new insights for electronic band structure by analyzing the Shubnikov-de Haas oscillations. Interestingly, the quantum oscillations are not 1∕B-periodic and produce a highly non-linear Landau plot (Landau level index versus 1/B). We explore different scenarios leading to 1/B-aperiodic oscillations where the charge and the chemical potential vary as the magnetic field increases. Overall, the magneto-transport data are discussed in light of high-resolution scanning transmission electron microscopy (HRSTEM) analysis of the interface as well as calculations from density functional theory.

尽管进行了几次尝试，但是埋藏在LaAlO ₃和SrTiO ₃之间的界面的二维电子系统的紧密电子结构仍有待实验证明。在这里，我们研究在高磁场（55 T）下该界面处的高迁移率准二维电子气的传输特性，并通过分析Shubnikov-de Haas振荡为电子能带结构提供新的见解。有趣的是，量子振荡不是1 ∕ B周期的，并产生高度非线性的Landau图（Landau能级指数与1 / B的关系）。我们探索导致1 / B的不同情况-非周期性振荡，其中电荷和化学势随磁场的增加而变化。总体而言，根据界面的高分辨率扫描透射电子显微镜（HRSTEM）分析以及根据密度泛函理论的计算，讨论了磁传输数据。