轴子耦合绝热泵浦的无隙铰链态
Gapless hinge states from adiabatic pumping of axion coupling
摘要：
我们表明，手征铰链模式自然出现在绝缘晶体进行缓慢的循环演变，改变陈-西蒙斯轴子角$θ$由$2π$。当表面（不仅仅是体）在循环结束时返回到其初始状态时，就会发生这种情况，在这种情况下，它必须通过金属状态来处理从体中泵出的表面异常霍尔电导率的多余量子。如果两个相邻的表面在沿着周期的不同点处变成金属，则存在一个间隔，在该间隔中它们处于拓扑上不同的绝缘状态，并且手征模式沿着连接铰链传播。我们说明了这些想法的紧束缚模型组成的耦合层的Halflit模型与交替参数。使用两种不同的标记，表面异常的霍尔电导率和表面本地化的电荷泵（流动的表面本地化的Wannier带）的表面拓扑结构确定在一个平板几何形状，我们发现，都正确地预测在杆几何形状的无间隙铰链模式的外观。当将轴子泵视为具有一个合成维度的四维（4D）晶体时，铰链模式在连接4D晶体的一对3D表面的2D铰链的布里渊区中追踪费米弧。
英文摘要：
We demonstrate that chiral hinge modes naturally emerge in insulating crystals undergoing a slow cyclic evolution that changes the Chern-Simons axion angle $θ$ by $2π$. This happens when the surface (not just the bulk) returns to its initial state at the end of the cycle, in which case it must pass through a metallic state to dispose of the excess quantum of surface anomalous Hall conductivity pumped from the bulk. If two adjacent surfaces become metallic at different points along the cycle, there is an interval in which they are in topologically distinct insulating states, with chiral modes propagating along the connecting hinge. We illustrate these ideas for a tight-binding model consisting of coupled layers of the Haldane model with alternating parameters. The surface topology is determined in a slab geometry using two different markers, surface anomalous Hall conductivity and surface-localized charge pumping (flow of surface-localized Wannier bands), and we find that both correctly predict the appearance of gapless hinge modes in a rod geometry. When viewing the axion pump as a four-dimensional (4D) crystal with one synthetic dimension, the hinge modes trace Fermi arcs in the Brillouin zone of the 2D hinge connecting a pair of 3D surfaces of the 4D crystal.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
