论文标题
Rashba Nanowire中Floquet Majorana模式的拓扑表征和稳定性
Topological characterization and stability of Floquet Majorana modes in Rashba nanowire
论文作者
论文摘要
从理论上讲,我们基于一维Rashba纳米线和接近度在Zeeman领域的存在下诱导了$ S $ - 波的超导性。驱动的系统托管常规$ 0 $ - 和异常$π$ -Majorana End Modes〜(MEMS)。通过调整化学电位和驱动器的频率,我们说明了理论设置中多个MEM的产生。我们利用手性对称性操作员通过由周期性进化运算符构建的动态绕组数来拓扑来表征这些MEM。有趣的是,在存在现场时间无关的随机疾病潜力的情况下,建立了$ 0 $ - 和$π$ -MEMS的鲁棒性。我们采用扭曲的边界条件来定义这种翻译对称破碎系统的动力拓扑不变。对于有限的驱动参数范围的动态绕组数量,Floquet驱动器与弱障碍之间的相互作用可以稳定MEMS的量化值。该观察结果可能在实验上有助于审查Floquet Mems的拓扑性质。我们展示了另一种驾驶协议,即,在我们的设置中研究Floquet Mems的化学潜力定期踢。我们的工作铺平了一种现实的方式,可以在驱动系统中设计多个内存。
We theoretically investigate a practically realizable Floquet topological superconductor model, based on a one-dimensional Rashba nanowire and proximity induced $s$-wave superconductivity in the presence of a Zeeman field. The driven system hosts regular $0$- and anomalous $π$-Majorana end modes~(MEMs). By tuning the chemical potential and the frequency of the drive, we illustrate the generation of multiple MEMs in our theoretical set up. We utilize the chiral symmetry operator to topologically characterize these MEMs via a dynamical winding number constructed out of the periodized evolution operator. Interestingly, the robustness of the $0$- and $π$-MEMs is established in the presence of on-site time-independent random disorder potential. We employ the twisted boundary condition to define the dynamical topological invariant for this translational-symmetry broken system. The interplay between the Floquet driving and the weak disorder can stabilize the MEMs giving rise to a quantized value of the dynamical winding number for a finite range of drive parameters. This observation might be experimentally helpful in scrutinizing the topological nature of the Floquet MEMs. We showcase another driving protocol namely, a periodic kick in the chemical potential to study the generation of Floquet MEMs in our setup. Our work paves a realistic way to engineer multiple MEMs in a driven system.