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arXiv · 2208.09346

Majorana edge-modes in a spinful particle conserving model

Franco T. Lisandrini·Corinna Kollath
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Abstract

We show the presence of Majorana edge modes in an interacting fermionic ladder with spin in a number conserved setting. The interchain single particle hopping is suppressed and only a pair hopping is present between the different chains of the ladder. Additionally, the hopping along the chains is spin imbalanced and a transverse magnetic field is applied breaking time-reversal invariance. We study the robustness of the topological phase with respect to an on-site interaction between the spin-up and spin-down fermions and the spin dependent imbalance of the hopping. The main result of the present work is that the topological phase survives for a finite region in the parameter space in the presence of interactions. The localized Majorana edge modes seems to be more stable in the case when the on-site interaction is an attraction.

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Franco T. Lisandrini, Corinna Kollath. 2022-11-17. Majorana edge-modes in a spinful particle conserving model. https://doi.org/10.1103/physrevb.106.245121

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