Single Skyrmion Generation Via a Vertical Nanocontact in a 2D Magnet-Based Heterostructure

Overview

Journal Nano Lett

Publisher American Chemical Society

Specialty Biotechnology

Date 2022 Nov 18

PMID 36400013

Authors

Lukas Powalla

Max T Birch

Kai Litzius

Sebastian Wintz

Frank Schulz

Markus Weigand

Tanja Scholz

Bettina V Lotsch

Klaus Kern

Gisela Schutz

Marko Burghard

Affiliations

Soon will be listed here.

Abstract

Skyrmions have been well studied in chiral magnets and magnetic thin films due to their potential application in practical devices. Recently, monochiral skyrmions have been observed in two-dimensional van der Waals magnets. Their atomically flat surfaces and capability to be stacked into heterostructures offer new prospects for skyrmion applications. However, the controlled local nucleation of skyrmions within these materials has yet to be realized. Here, we utilize real-space X-ray microscopy to investigate a heterostructure composed of the 2D ferromagnet FeGeTe (FGT), an insulating hexagonal boron nitride layer, and a graphite top electrode. Upon a stepwise increase of the voltage applied between the graphite and FGT, a vertically conducting pathway can be formed. This nanocontact allows the tunable creation of individual skyrmions via single nanosecond pulses of low current density. Furthermore, time-resolved magnetic imaging highlights the stability of the nanocontact, while our micromagnetic simulations reproduce the observed skyrmion nucleation process.

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