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arXiv · 2205.11222

Stability of Majorana Edge Zero Modes against Interactions

Tohru Koma
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Abstract

We study an interacting Majorana chain with an open boundary condition. In the case without interactions, the system shows a prototypical Majorana edge zero mode in the sector of the ground state with a spectral gap above the sector. We prove that both of the Majorana edge zero mode and the non-vanishing spectral gap are stable against generic weak interactions whose fermion parity is even. We also deal with the corresponding ladder systems, and discuss the $\mathbb{Z}_2$ index for the Majorana edge zero modes.

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Tohru Koma. 2022-05-23. Stability of Majorana Edge Zero Modes against Interactions. https://arxiv.org/abs/2205.11222

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