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arXiv · 1712.07625

Interaction-induced zero-energy pinning and quantum dot formation in Majorana nanowires

Samuel D. Escribano·Alfredo Levy Yeyati·Elsa Prada
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Abstract

Majorana modes emerge in non-trivial topological phases at the edges of some specific materials, like proximitized semiconducting nanowires under a external magnetic field. Ideally, they are non-local states that are charge neutral superpositions of electrons and holes. However, in nanowires of realistic length their wave functions overlap and acquire a finite charge that, under certain circumstances, makes them susceptible to interactions, specifically with the image charges that arise in the electrostatic environment. Considering a realistic three-dimensional model of the dielectric surroundings, here we show that this interaction leads to a suppression of the Majorana oscillations predicted by simpler theoretical models, and to the formation of low-energy quantum dot states that interact with the Majorana modes. Both features are observed in recent experiments on the detection of Majoranas and could thus help to properly characterize them.

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Samuel D. Escribano, Alfredo Levy Yeyati, Elsa Prada. 2018-09-12. Interaction-induced zero-energy pinning and quantum dot formation in Majorana nanowires. https://doi.org/10.3762/bjnano.9.203

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