Signatures of Majorana bound states and parity effects in two-dimensional chiral p -wave Josephson junctions
Signatures of Majorana bound states and parity effects in two-dimensional chiral p -wave Josephson junctions
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DOI：
10.1103/physrevb.105.214521
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发表时间：
2022-02
影响因子：
3.7
通讯作者：
Nick Abboud;V. Subramanyan;Xiao-Qi Sun;G. Yue;D. V. Van Harlingen;S. Vishveshwara
中科院分区：
文献类型：
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作者：
Nick Abboud;V. Subramanyan;Xiao-Qi Sun;G. Yue;D. V. Van Harlingen;S. Vishveshwara
本文描述了介观手征p波超导岛耦合约瑟夫森结的拓扑结构.通过分析和数值研究的低洼BdG（Bogoliubov-de Gennes）的频谱，我们确定本地MBS（马约拉纳束缚态）成核的约瑟夫森涡旋的应用程序的垂直磁场。此外，我们证明了一个扩展的MBS的存在，是离域周围的耦合岛，这对约瑟夫森超导和相位动力学的结的外周界有可测量的后果。特别是，我们预测的变化，在临界电流衍射图案中，奇数整数通量节点被解除费米子宇称依赖的方式。我们的竞争随机效应的热噪声和宏观量子隧穿RCSJ框架内的模型，并显示了双峰临界电流分布的出现。我们表明，增加宇称跃迁率抑制双峰性质的分布，从而强烈强调了非平凡的宇称依赖性质的多体基态。最后，我们考虑了三个岛屿的三结几何形状，并讨论了可能的方案编织马约拉纳束缚态移动的约瑟夫森涡，他们绑定。
We characterize topological features of Josephson junctions formed by coupled mesoscopic chiral $p$-wave superconducting islands. Through analytic and numerical studies of the low-lying BdG (Bogoliubov-de Gennes) spectrum, we identify localized MBS (Majorana bound states) nucleated in Josephson vortices by the application of a perpendicular magnetic field. Additionally, we demonstrate the existence of an extended MBS that is delocalized around the outer perimeter of the coupled islands, which has measurable consequences on the Josephson supercurrent and phase dynamics of the junction. In particular, we predict a change in the critical current diffraction pattern in which the odd integer-flux nodes are lifted in a fermion parity-dependent fashion. We model the competing stochastic effects of thermal noise and macroscopic quantum tunneling within the RCSJ framework and show the emergence of a bimodal critical current distribution. We demonstrate that increasing the parity transition rate suppresses the bimodal nature of the distribution, thus strongly emphasizing the non-trivial parity dependent nature of the many-body ground state. Finally, we consider a trijunction geometry with three islands and discuss possible schemes to braid Majorana bound states by moving the Josephson vortices to which they are bound.