AI 中文总结
本文针对手征超导纳米线，提出通过手征分量空间重叠诊断低能态抗无序性的机制，揭示平滑限域产生的类马约拉纳态可抵御强非磁性无序。
AI 中文摘要
马约拉纳纳米线中的近零能态可由拓扑平庸机制产生，如平滑空间不均匀性和无序，仅零能钉扎不足以作为体拓扑的证据。本文确定了一种决定其对对称性保持无序鲁棒性的实空间机制：对手征对称的Bogoliubov-de Gennes哈密顿量，将低能态分解为两个归一化的相反手征分量，证明无序诱导的分裂受限于它们的空间重叠。在具有平滑化学势和配对分布的有限Rashba纳米线中，本文展示了该结果：在体拓扑相变以下，平滑限域产生部分分离的手征分量，其指数小的重叠产生全局平庸的类马约拉纳安德烈夫束缚态，即使在强标量非磁性无序下仍保持近零能。因此，手征重叠提供了一种独立于体拓扑不变量的、对低能态抵御局域微扰的保护的直接诊断方法。
英文摘要
Near-zero-energy states in Majorana nanowires can arise from topologically trivial mechanisms such as smooth spatial inhomogeneity and disorder, making zero-energy pinning alone insufficient evidence of bulk topology. Here we identify a real-space mechanism governing their robustness to symmetry-preserving disorder. For a chiral-symmetric Bogoliubov-de Gennes Hamiltonian, we decompose a low-energy state into two normalized components of opposite chirality and show that disorder-induced splitting is bounded by their spatial overlap. We demonstrate this result in a finite Rashba nanowire with smooth chemical potential and pairing profiles. Below the bulk topological transition, smooth confinement produces partially separated chiral components with exponentially small overlap, yielding globally trivial Majorana-like Andreev bound states that remain near zero energy even under strong scalar, nonmagnetic disorder. The chiral overlap therefore provides a direct diagnostic of the protection of low-energy states against local perturbations, independent of the bulk topological invariant.
Comments13 pages, 8 figures. Comments welcome
