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arXiv · 2105.11199

Unveiling non-Abelian statistics of vortex Majorana bound states in iron-based superconductors using fermionic modes

Abstract

Motivated by the recent experiments that reported the discovery of vortex Majorana bound states (vMBSs) in iron-based superconductors, we establish a portable scheme to unveil the non-Abelian statistics of vMBSs using normal fermionic modes. The unique non-Abelian statistics of vMBSs is characterized by the charge flip signal of the fermions that can be easily read out through the charge sensing measurement. In particular, the charge flip signal will be significantly suppressed for strong hybridized vMBSs or trivial vortex modes, which efficiently identifies genuine vMBSs. To eliminate the error induced by the unnecessary dynamical evolution of the fermionic modes, we further propose a correction strategy by continually reversing the energy of the fermions, reminiscent of the quantum Zeno effect. Finally, we establish a feasible protocol to perform non-Abelian braiding operations on vMBSs.

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Ming Gong, Yijia Wu, Hua Jiang, Jie Liu, X. C. Xie. 2021-05-24. Unveiling non-Abelian statistics of vortex Majorana bound states in iron-based superconductors using fermionic modes. https://doi.org/10.1103/physrevb.105.014507

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