论文标题
二维平固体中的量子几何振荡
Quantum Geometric Oscillations in Two-Dimensional Flat-Band Solids
论文作者
论文摘要
二维范德华异质结构可以设计成具有明显浆果曲率的平坦带，并为新型电子动力学的出现提供了有利的环境。特别是，浆果曲率可以诱导电子波包横向到施加的静态电场的电子波包的振荡轨迹。尽管类似于Bloch振荡，但这种新颖的振荡行为完全由动量空间中的量子几何形状驱动，而不是带分散。尽管Bloch振荡的轨道可以通过增加场强度来定位，但几何轨道的大小在强场极限下饱和到非零高原。在非磁性材料中，几何振荡甚至在应用领域的反转下，而Bloch振荡很奇怪，该特性可用于区分这两个共存效应。
Two-dimensional van der Waals heterostructures can be engineered into artificial superlattices that host flat bands with significant Berry curvature and provide a favorable environment for the emergence of novel electron dynamics. In particular, the Berry curvature can induce an oscillating trajectory of an electron wave packet transverse to an applied static electric field. Though analogous to Bloch oscillations, this novel oscillatory behavior is driven entirely by quantum geometry in momentum space instead of band dispersion. While the orbits of Bloch oscillations can be localized by increasing field strength, the size of the geometric orbits saturates to a nonzero plateau in the strong-field limit. In non-magnetic materials, the geometric oscillations are even under inversion of the applied field, whereas the Bloch oscillations are odd, a property that can be used to distinguish these two co-existing effects.
