Zhou Tong, Dartiailh Matthieu C, Mayer William, Han Jong E, Matos-Abiague Alex, Shabani Javad, Žutić Igor
Department of Physics, University at Buffalo, State University of New York, Buffalo, New York 14260, USA.
Center for Quantum Phenomena, Department of Physics, New York University, New York, New York 10003, USA.
Phys Rev Lett. 2020 Apr 3;124(13):137001. doi: 10.1103/PhysRevLett.124.137001.
Topological superconductivity supports exotic Majorana bound states (MBS) which are chargeless zero-energy emergent quasiparticles. With their non-Abelian exchange statistics and fractionalization of a single electron stored nonlocally as a spatially separated MBS, they are particularly suitable for implementing fault-tolerant topological quantum computing. While realizing MBS has focused on one-dimensional systems, the onset of topological superconductivity requires delicate parameter tuning and geometric constraints pose significant challenges for their control and demonstration of non-Abelian statistics. To overcome these challenges, building on recent experiments in planar Josephson junctions (JJs), we propose a MBS platform of X-shaped JJs. This versatile implementation reveals how external flux control of the superconducting phase difference can generate and manipulate multiple MBS pairs to probe non-Abelian statistics. The underlying topological superconductivity exists over a large parameter space, consistent with materials used in our fabrication of such X junctions, as an important step towards scalable topological quantum computing.
拓扑超导支持奇异的马约拉纳束缚态（MBS），它是无电荷的零能涌现准粒子。由于其非阿贝尔交换统计特性以及单个电子以空间分离的MBS形式非局域存储的分数化特性，它们特别适合用于实现容错拓扑量子计算。虽然实现MBS主要集中在一维系统上，但拓扑超导的出现需要精确的参数调整，并且几何约束对其控制和非阿贝尔统计的证明构成了重大挑战。为了克服这些挑战，基于平面约瑟夫森结（JJ）的最新实验，我们提出了一个X形JJ的MBS平台。这种通用的实现方式揭示了超导相位差的外部磁通控制如何产生和操纵多个MBS对，以探测非阿贝尔统计。潜在的拓扑超导存在于一个大的参数空间中，这与我们制造此类X结所使用的材料一致，是迈向可扩展拓扑量子计算的重要一步。
