Zhao Pai, Sharma Chithra H, Liang Renrong, Glasenapp Christian, Mourokh Lev, Kovalev Vadim M, Huber Patrick, Prada Marta, Tiemann Lars, Blick Robert H
Center for Hybrid Nanostructures, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany.
School of Integrated Circuits, Tsinghua University, 100084 Beijing, China.
Phys Rev Lett. 2022 Jun 24;128(25):256601. doi: 10.1103/PhysRevLett.128.256601.
Any departure from graphene's flatness leads to the emergence of artificial gauge fields that act on the motion of the Dirac fermions through an associated pseudomagnetic field. Here, we demonstrate the tunability of strong gauge fields in nonlocal experiments using a large planar graphene sheet that conforms to the deformation of a piezoelectric layer by a surface acoustic wave. The acoustic wave induces a longitudinal and a giant synthetic Hall voltage in the absence of external magnetic fields. The superposition of a synthetic Hall potential and a conventional Hall voltage can annihilate the sample's transverse potential at large external magnetic fields. Surface acoustic waves thus provide a promising and facile avenue for the exploitation of gauge fields in large planar graphene systems.
石墨烯平整度的任何偏离都会导致人工规范场的出现,这些规范场通过相关的赝磁场作用于狄拉克费米子的运动。在此,我们通过使用一个大的平面石墨烯片,在非局部实验中证明了强规范场的可调性,该石墨烯片会随着表面声波使压电层发生形变。在没有外部磁场的情况下,声波会诱导出纵向和巨大的合成霍尔电压。在强外部磁场下,合成霍尔电势与传统霍尔电压的叠加可以消除样品的横向电势。因此,表面声波为在大型平面石墨烯系统中利用规范场提供了一条有前景且便捷的途径。