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arXiv · 1806.05025

Detecting topological phases via survival probabilities of edge Majorana fermions

Yucheng Wang
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Abstract

We investigate the evolutions of edge Majorana fermions (MFs) and unveil that they can be used to char- acterize different topological phases and study the topological phase transitions. For some limiting cases of the evolution process for the one-dimensional Kitaev model and Su-Schrieffer-Heeger (SSH) model, we give analytical expressions of the survival probabilities of the edge MFs, which indicates that different topological phases correspond to different zero point numbers of the defined survival probabilities at some times. For a general case, we consider a dimerized Kitaev model and the Kitaev chain with disorder chemical potential and numerically calculate the survival probabilities of two edge correlation MFs. Our results show that both of them equal to zero, one of them equals to zero at some times or neither of them equal to zero correspond to the SSH-like topological, topological superconductor and trivial phases respectively.

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Yucheng Wang. 2018-10-17. Detecting topological phases via survival probabilities of edge Majorana fermions. https://doi.org/10.1103/physreve.98.042128

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