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arXiv · 2303.01535

Perfectly localized Majorana corner modes in fermionic lattices

Prathyush P. Poduval·Thomas L. Schmidt·Andreas Haller
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Abstract

Focusing on examples of Majorana zero modes on the corners of a two-dimensional lattice, we introduce a method to find parameter regions where the Majorana modes are perfectly localized on a single site. Such a limit allows us to study the dimerization structure of the sparse bulk Hamiltonian that results in the higher-order topology of the system. Furthermore, such limits typically provide an analytical understanding of the system energy scales. Based on the dimerization structure we extract from the two-dimensional model, we identify a more general stacking procedure to construct Majorana zero modes in arbitrary corners of a $d$-dimensional hypercube, which we demonstrate explicitly in $d\leq3$.

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Prathyush P. Poduval, Thomas L. Schmidt, Andreas Haller. 2023-03-02. Perfectly localized Majorana corner modes in fermionic lattices. https://doi.org/10.1103/physrevb.108.035124

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