论文标题
在整数磁通量中的扭曲双层石墨烯中的重点魔法角度现象
Re-entrant magic-angle phenomena in twisted bilayer graphene in integer magnetic fluxes
论文作者
论文摘要
在这项工作中，我们解决了扭曲的双层石墨烯（TBG）（TBG）的魔法现象（频带平坦和量子几何传输）的重新进入，受到强磁通量的$ \ pmφ_0$，$ \ pm \ pm pm2φ_0$，$ \ pm \ pm3φ_0$ ...（$φ_0$ ... Moiré翻译不变性在整数通量上恢复，为此，我们使用具有晶格弛豫的精确原子模型来计算TBG带的结构。与魔术角条件之外的零频道物理类似，报告的效果随着扭曲而迅速分解。我们得出的结论是，高磁场中的魔法物理学重新出现，这是由于与Landau水平不同的平坦电子带的出现而见证的，并表现出非平凡的量子几何形状。根据Peotta-Törmä机制，我们进一步讨论了强磁场中可能对超流量重量的平坦量子几何贡献。
In this work we address the re-entrance of magic-angle phenomena (band flatness and quantum-geometric transport) in twisted bilayer graphene (TBG) subjected to strong magnetic fluxes $\pm Φ_0$, $\pm 2 Φ_0$, $\pm 3 Φ_0$... ($Φ_0 = h/e$ is the flux quantum per moiré cell). The moiré translation invariance is restored at the integer fluxes, for which we calculate the TBG band structure using accurate atomistic models with lattice relaxations. Similarly to the zero-flux physics outside the magic angle condition, the reported effect breaks down rapidly with the twist. We conclude that the magic-angle physics re-emerges in high magnetic fields, witnessed by the appearance of flat electronic bands distinct from Landau levels, and manifesting non-trivial quantum geometry. We further discuss the possible flat-band quantum geometric contribution to the superfluid weight in strong magnetic fields (28 T at 1.08$^\circ$ twist), according to Peotta-Törmä mechanism.
