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Large spatial extension of the zero-energy Yu-Shiba-Rusinov state in a magnetic field.

ABSTRACT: Various promising qubit concepts have been put forward recently based on engineered superconductor subgap states like Andreev bound states, Majorana zero modes or the Yu-Shiba-Rusinov (Shiba) states. The coupling of these subgap states via a superconductor strongly depends on their spatial extension and is an essential next step for future quantum technologies. Here we investigate the spatial extension of a Shiba state in a semiconductor quantum dot coupled to a superconductor. With detailed transport measurements and numerical renormalization group calculations we find a remarkable more than 50?nm extension of the zero energy Shiba state, much larger than the one observed in very recent scanning tunneling microscopy measurements. Moreover, we demonstrate that its spatial extension increases substantially in a magnetic field.

SUBMITTER: Scherubl Z

PROVIDER: S-EPMC7156378 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Large spatial extension of the zero-energy Yu-Shiba-Rusinov state in a magnetic field.

Scherübl Zoltán Z Fülöp Gergő G Moca Cătălin Paşcu CP Gramich Jörg J Baumgartner Andreas A Makk Péter P Elalaily Tosson T Schönenberger Christian C Nygård Jesper J Zaránd Gergely G Csonka Szabolcs S

Nature communications 20200414 1

Various promising qubit concepts have been put forward recently based on engineered superconductor subgap states like Andreev bound states, Majorana zero modes or the Yu-Shiba-Rusinov (Shiba) states. The coupling of these subgap states via a superconductor strongly depends on their spatial extension and is an essential next step for future quantum technologies. Here we investigate the spatial extension of a Shiba state in a semiconductor quantum dot coupled to a superconductor. With detailed tra ...[more]

PMID: 32286260

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