标题： 声电超晶格 显示英文标题

标题： Acoustoelectric superlattices

摘要： 我们引入了一类可调节的周期性结构，该结构由在支持二维量子材料的压电基底上激发两个斜向传播的表面声波形成。 所产生的声电超晶格表现出两个显著特征。 首先，其周期性具有广泛的可调性，跨越了莫尔超晶格和光晶格之间的长度尺度，能够形成窄的、拓扑非平凡的能量带。 其次，与莫尔系统不同，莫尔系统的超晶格振幅由层间隧穿和晶格弛豫的内在特性决定，而声电势的振幅则可以通过表面声波功率进行外部调节。 以大量单层石墨烯为例，我们证明了改变表面声波的频率和功率可以实现对二维材料能带结构的原位控制，生成平带和非平凡的谷陈数，具有高度局域化的贝里曲率。 显示英文摘要

摘要： We introduce a new class of tunable periodic structures, formed by launching two obliquely propagating surface acoustic waves on a piezoelectric substrate that supports a two-dimensional quantum material. The resulting acoustoelectric superlattice exhibits two salient features. First, its periodicity is widely tunable, spanning a length scale intermediate between moir\'e superlattices and optical lattices, enabling the formation of narrow, topologically nontrivial energy bands. Second, unlike moir\'e systems, where the superlattice amplitude is set by intrinsic interlayer tunneling and lattice relaxation, the amplitude of the acoustoelectric potential is externally tunable via the surface acoustic wave power. Using massive monolayer graphene as an example, we demonstrate that varying the frequencies and power of the surface acoustic waves enables in-situ control over the band structure of the 2D material, generating flat bands and nontrivial valley Chern numbers, featuring a highly localized Berry curvature.