Moiré-Enabled Topological Superconductivity.

Shawulienu Kezilebieke,Markus Aapro,Peter Liljeroth,Jose L Lado,Viliam Vaňo,Md N Huda,Somesh C Ganguli

doi:10.1021/acs.nanolett.1c03856

Shawulienu Kezilebieke, Markus Aapro + Show 5 more

Open Access

https://doi.org/10.1021/acs.nanolett.1c03856

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Journal: Nano letters	Publication Date: Jan 3, 2022
Citations: 30	License type: CC BY 4.0

Affiliation: University of Jyväskylä, Aalto University

Abstract

The search for artificial topological superconductivity has been limited by the stringent conditions required for its emergence. As exemplified by the recent discoveries of various correlated electronic states in twisted van der Waals materials, moiré patterns can act as a powerful knob to create artificial electronic structures. Here, we demonstrate that a moiré pattern between a van der Waals superconductor and a monolayer ferromagnet creates a periodic potential modulation that enables the realization of a topological superconducting state that would not be accessible in the absence of the moiré. The magnetic moiré pattern gives rise to Yu–Shiba–Rusinov minibands and periodic modulation of the Majorana edge modes that we detect using low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS). Moiré patterns and, more broadly, periodic potential modulations are powerful tools to overcome the conventional constraints for realizing and controlling topological superconductivity.

Highlights

The search for artificial topological superconductivity has been limited by the stringent conditions required for its emergence
T here are many routes to realizing topological superconductivity in artificial structures,[1−10] and perhaps the most widely used path uses the combination of superconductivity, spin−orbit coupling, and magnetism.[11,12]
It is surprising that such complex electronic structure with no external control parameters turns out to give rise to a state featuring topological superconductivity

Summary

Introduction

The search for artificial topological superconductivity has been limited by the stringent conditions required for its emergence. The strongly modulated electrostatic potential and exchange coupling in the moiré heterostructure give rise to modulated Yu−Shiba−Rusinov (YSR) bands that allow for the emergence of topological superconductivity in generic regimes where it is otherwise forbidden.

Results

Conclusion