Quantum dot detects Majorana modes of both chiralities

Piotr Stefański

doi:10.1016/j.jmmm.2023.171067

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arXiv · 2307.13366

Quantum dot detects Majorana modes of both chiralities

Piotr Stefański

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Abstract

A tunneling junction between normal electrode and a topological superconducting wire, mediated by a quantum dot, is considered theoretically. We show that the presence of the dot in the junction can be advantageous to Majorana zero modes identification. Namely, we demonstrate that for the dot strongly coupled to the wire, the Majorana mode from the upper chiral sub-band "leaks" into the dot, providing supplementary information on Majorana mode formation. Thus, both the Zeeman-split dot sub-levels detect Majorana partners of a Kramers pair, formed at the wire end. The characteristic three-peak structures in both spin sectors of the spectral density of the dot, distinguish from the trivial scenario of one Andreev resonance at Fermi energy produced exclusively by the dot's spin sub-levels.

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Piotr Stefański. 2023-07-25. Quantum dot detects Majorana modes of both chiralities. https://doi.org/10.1016/j.jmmm.2023.171067

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