Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Nat Commun. 2012 Jul 17;3:964. doi: 10.1038/ncomms1966.
Semiconducting nanowires in proximity to superconductors are promising experimental systems for realizing the elusive Majorana fermions, which, because of their non-abelian anyonic braiding statistics, may ultimately be used as building blocks for topological quantum computers. A serious challenge in the experimental realization of the Majorana fermions is the suppression of topological superconductivity by disorder together with the tunability of carrier density for semiconductors in close proximity to superconductors. Here we show that Majorana fermions that are protected by a disorder robust topological gap can occur at the ends of a chain of gate-tunable quantum dots connected by s-wave superconductors. Such an array of quantum dots provides the simplest realization of Majorana fermions in systems as simple as a few quantum dot array. The proposed system provides a very practical and easily realizable experimental platform for the observation of non-abelian Majorana modes.
半导体纳米线与超导体接近是实现难以捉摸的马约拉纳费米子的有前途的实验系统，由于其非阿贝尔任意子编织统计，最终可能被用作拓扑量子计算机的构建块。在马约拉纳费米子的实验实现中，一个严重的挑战是通过无序来抑制拓扑超导，同时还要调节与超导体接近的半导体的载流子密度。在这里，我们表明，由无序鲁棒拓扑间隙保护的马约拉纳费米子可以出现在由 s 波超导体连接的门可调量子点链的末端。这种量子点阵列提供了最简单的马约拉纳费米子在像几个量子点阵列这样简单的系统中的实现。所提出的系统为观察非阿贝尔马约拉纳模式提供了一个非常实用且易于实现的实验平台。
