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Sub-Band Spectrum Engineering via Structural Order in Tapered Nanowires.

ABSTRACT: The cross-sectional dimensions of nanowires set the quantization conditions for the electronic subbands they host. These can be used as a platform to realize one-dimesional topological superconductivity. Here we develop a protocol that forces such nanowires to kink and change their growth direction. Consequently, a thin rectangular nanoplate is formed, which gradually converges into a very thin square tip. We characterize the resulting tapered nanowires structurally and spectroscopically by scanning and transmission electron microscopy and scanning tunneling microscopy and spectroscopy and model their growth. A unique structure composed of ordered rows of atoms on the (110) facet of the nanoflag is further revealed by atomically resolved topography and modeled by simulations. We discuss possible advantages tapered InAs nanowires offer for Majorana zero-mode realization and manipulation.

SUBMITTER: Song MS

PROVIDER: S-EPMC8704197 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Sub-Band Spectrum Engineering via Structural Order in Tapered Nanowires.

Song Man Suk MS Koren Tom T Załuska-Kotur Magdalena M Buczko Ryszard R Avraham Nurit N Kacman Perla P Shtrikman Hadas H Beidenkopf Haim H

Nano letters 20211209 24

The cross-sectional dimensions of nanowires set the quantization conditions for the electronic subbands they host. These can be used as a platform to realize one-dimesional topological superconductivity. Here we develop a protocol that forces such nanowires to kink and change their growth direction. Consequently, a thin rectangular nanoplate is formed, which gradually converges into a very thin square tip. We characterize the resulting tapered nanowires structurally and spectroscopically by scan ...[more]

PMID: 34882412

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