论文标题
来自三维耦合线结构的二阶拓扑绝缘子的分数二阶绝缘体
Fractional second-order topological insulator from a three-dimensional coupled-wires construction
论文作者
论文摘要
我们从一系列弱隧道耦合的rashba纳米线中构建了一个三维二阶拓扑绝缘子，并用无间隙的螺旋铰链状态构建。对于适当选择的Interwire隧道，我们证明该系统具有完全散发的大体和完全间隙的表面，但是托管了一对kramers对无间隙的螺旋铰链状态，沿着铰链沿铰链的路径传播，该路径由Interwire Tunnelings的层次结构和系统的边界终止确定。此外，耦合线方法使我们能够将电子电子相互作用纳入我们的描述。在单个电线的合适填充因子下，我们表明，足够强的电子电子相互作用可以将系统带入一个二阶拓扑绝缘子相，其铰链状态仅携带奇数$ p $的电子电荷$ e $的分数$ e/p $。
We construct a three-dimensional second-order topological insulator with gapless helical hinge states from an array of weakly tunnel-coupled Rashba nanowires. For suitably chosen interwire tunnelings, we demonstrate that the system has a fully gapped bulk as well as fully gapped surfaces, but hosts a Kramers pair of gapless helical hinge states propagating along a path of hinges that is determined by the hierarchy of interwire tunnelings and the boundary termination of the system. Furthermore, the coupled-wires approach allows us to incorporate electron-electron interactions into our description. At suitable filling factors of the individual wires, we show that sufficiently strong electron-electron interactions can drive the system into a fractional second-order topological insulator phase with hinge states carrying only a fraction $e/p$ of the electronic charge $e$ for an odd integer $p$.
