Controlling Fusion of Majorana Fermions in one-dimensional systems by Zeeman Field

L. B. Shao; Z. D. Wang; R. Shen; L. Sheng; B. G. Wang; D. Y. Xing

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arXiv · 1304.4726

Controlling Fusion of Majorana Fermions in one-dimensional systems by Zeeman Field

L. B. Shao·Z. D. Wang·R. Shen·L. Sheng·B. G. Wang·D. Y. Xing

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Abstract

We propose to realize Majorana fermions (MFs) on an edge of a two-dimensional topological insulator in the proximity with s-wave superconductors and in the presence of transverse exchange field h. It is shown that there appear a pair of MFs localized at two junctions and that a reverse in direction of h can lead to permutation of two MFs. With decreasing h, the MF states can either be fused or form one Dirac fermion on the {\pi}-junctions, exhibiting a topological phase transition. This characteristic can be used to detect physical states of MFs when they are transformed into Dirac fermions localized on the {\pi}-junction. A condition of decoupling two MFs is also given.

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L. B. Shao, Z. D. Wang, R. Shen, L. Sheng, B. G. Wang, D. Y. Xing. 2013-04-17. Controlling Fusion of Majorana Fermions in one-dimensional systems by Zeeman Field. https://arxiv.org/abs/1304.4726

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