Atomically sharp 1D interfaces in 2D lateral heterostructures of VSe$_2$-NbSe$_2$ monolayers

TL;DR

This paper reports the successful synthesis and characterization of atomically sharp 1D interfaces in lateral heterostructures of VSe₂ and NbSe₂ monolayers, revealing novel electronic states and Kondo resonances.

Contribution

It introduces a new one-pot two-step molecular beam epitaxy method to create defect-free, atomically sharp lateral heterostructures of VSe₂ and NbSe₂ monolayers.

Findings

Formation of defect-free lateral heterostructures confirmed by microscopy.

Observation of additional electronic states at the 1D interface.

Detection of Kondo resonances in the heterostructures.

Abstract

Van der Waals heterostructures have emerged as an ideal platform for creating engineered artificial electronic states. While vertical heterostructures have been extensively studied, realizing high-quality lateral heterostructures with atomically sharp interfaces remains a major experimental challenge. Here, we advance a one-pot two-step molecular beam lateral epitaxy approach and successfully synthesize atomically well-defined 1T-VSe$_2$ -- 1H-NbSe$_2$ lateral heterostructures. We demonstrate the formation of defect-free lateral heterostructures and characterize their electronic structure using scanning tunnelling microscopy and spectroscopy together with density functional theory calculations. We find additional electronic states at the one-dimensional interface as well as signatures of Kondo resonances in a side-coupled geometry. Our experiments explore the full potential of lateral heterostructures for realizing exotic electronic states in low-dimensional systems for further studies of artificial designer quantum materials.