论文标题
魔术角振动板中的平坦乐队
Flat bands in magic-angle vibrating plates
论文作者
论文摘要
扭曲的双层石墨烯通过与载体手性相关的非常规机构在特定的“魔法”层间旋转角以特定的“魔术”中旋转角形成了准平线带。准燃料频段负责系统中的许多异国情调,相关的电子阶段。在这项工作中,我们提出了由两个振动板制成的扭曲双层石墨烯的机械类似物,该石墨烯用蜂窝状的质量构成了蜂窝状网格,并在连续弹性介质中偶联。我们表明,设备中的弯曲波在魔法角度表现出消失的组速度和准平线带,并与石墨烯模型中的电子密切对应。两个系统中光谱结构和空间本征的强烈相似性证明了机械平面带的手性质。我们得出了定量连接机械和电子模型的分析表达式,这使我们能够预测实现建议的实验所需的参数。
Twisted bilayer graphene develop quasi-flat bands at specific "magic" interlayer rotation angles through an unconventional mechanism connected to carrier chirality. Quasi-flat bands are responsible for a wealth of exotic, correlated-electron phases in the system. In this work we propose a mechanical analogue of twisted bilayer graphene made of two vibrating plates, patterned with a honeycomb mesh of masses, and coupled across a continuum elastic medium. We show that flexural waves in the device exhibit vanishing group velocity and quasi-flat bands at magic angles, in close correspondence with electrons in graphene models. The strong similarities of spectral structure and spatial eigenmodes in the two systems demonstrate the chiral nature of the mechanical flat bands. We derive analytical expressions that quantitatively connect the mechanical and electronic models, which allow us to predict the parameters required for an experimental realization of our proposal.