论文标题
Majoraana在有抗铁磁秩序的情况下,在超导的Rashba纳米线中绑定了状态
Majorana bound states in a superconducting Rashba nanowire in the presence of antiferromagnetic order
论文作者
论文摘要
理论研究表明,Majorana结合状态可以在一维线的末端诱导,这是由于S波超导性,自旋轨道耦合和外部磁场之间的相互作用而导致的现象。这些状态在存在Zeeman场的存在和低密度颗粒的极限的情况下,在超导体 - 触发器杂种纳米结构中观察到了这些状态。在本文中,我们演示并讨论了主要导向在抗铁磁性有序表面上的超导rashba纳米线中出现的可能性。我们以几种互补的方式计算相关的拓扑不变。研究拓扑相图揭示了非琐碎拓扑阶段的两个分支 - 一个主要分支,这是Rashba纳米线的典型分支,并且由于抗磁磁性顺序而出现了附加的分支。在附加的拓扑分支的情况下,Majorana结合状态也可能存在接近半填充,从而消除了需要掺杂或门控纳米线以达到低密度状态的需求。此外,我们在没有外部磁场的情况下显示了主要结合状态的出现,这是由于抗磁磁性的。我们还讨论了在真实空间定位和系统的光谱函数的背景下结合状态的属性。这使人们可以在附加分支中的自旋和sublattice子空间内感知频段反转,这与主分支相反,在该分支中,在以前的研究中,唯一在自旋子空间中存在的频段反转。最后,我们证明了如何在运输测量中实验确认这些拓扑阶段。
Theoretical studies have shown that Majorana bound states can be induced at the ends of a one dimensional wire, a phenomenon possible due to the interplay between s-wave superconductivity, spin-orbit coupling, and an external magnetic field. These states have been observed in superconductor-semiconductor hybrid nanostructures in the presence of a Zeeman field, and in the limit of a low density of particles. In this paper, we demonstrate and discuss the possibility of the emergence of Majorana bound states in a superconducting Rashba nanowire deposited on an antiferromagnetically ordered surface. We calculate the relevant topological invariant in several complementary ways. Studying the topological phase diagram reveals two branches of the non trivial topological phase -- a main branch, which is typical for Rashba nanowires, and an additional branch emerging due to the antiferromagnetic order. In the case of the additional topological branch, Majorana bound states can also exist close to half-filling, obviating the need for either doping or gating the nanowire to reach the low density regime. Moreover, we show the emergence of the Majorana bound states in the absence of the external magnetic field, which is possible due to the antiferromagnetic order. We also discuss the properties of the bound states in the context of real space localization and the spectral function of the system. This allows one to perceive the band inversion within the spin and sublattice subspaces in the additional branch, contrary to the main branch, where the only band inversion reported in previous studies exists in the spin subspace. Finally, we demonstrate how these topological phases can be confirmed experimentally in transport measurements.