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

ABSTRACT: Majorana modes emerge in non-trivial topological phases at the edges of specific materials such as proximitized semiconducting nanowires under an 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 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, under certain circumstances, these interactions lead 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.

SUBMITTER: Escribano SD

PROVIDER: S-EPMC6122061 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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

Escribano Samuel D SD Yeyati Alfredo Levy AL Prada Elsa E

Beilstein journal of nanotechnology 20180815

Majorana modes emerge in non-trivial topological phases at the edges of specific materials such as proximitized semiconducting nanowires under an 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 makes them susceptible to interactions, specifically with the image charges that arise in the electrostatic environment. Consid ...[more]

PMID: 30202687

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