Controllable dimensionality conversion between 1D and 2D CrCl3 magnetic nanostructures

TL;DR

This paper demonstrates the controlled fabrication and transformation of 1D CrCl3 atomic wires into 2D layers on a van der Waals superconductor, revealing new magnetic states and interfacial effects.

Contribution

It introduces a method to create and switch between 1D and 2D CrCl3 magnetic nanostructures on a vdW substrate, highlighting the role of interfacial interactions.

Findings

1D CrCl3 wires are antiferromagnetic semiconductors.

Transformation between 1D and 2D phases can be controlled in situ.

Interfacial electronic interactions regulate dimensionality conversion.

Abstract

The fabrication of one-dimensional (1D) magnetic systems on solid surfaces, although of high fundamental interest, has yet to be achieved for a crossover between two-dimensional (2D) magnetic layers and their associated 1D spin chain systems. In this study, we report the fabrication of 1D single-unit-cell-width CrCl3 atomic wires and their stacked few-wire arrays on the surface of a van der Waals (vdW) superconductor NbSe2. Scanning tunneling microscopy/spectroscopy and first-principles calculations jointly revealed that the single wire shows an antiferromagnetic large-bandgap semiconducting state in an unexplored structure different from the well-known 2D CrCl3 phase. Competition among the total energies and nanostructure-substrate interfacial interactions of these two phases result in the appearance of the 1D phase. This phase was transformable to the 2D phase either prior to or after the growth for in situ or ex situ manipulations, in which the electronic interactions at the vdW interface play a nontrivial role that could regulate the dimensionality conversion and structural transformation between the 1D-2D CrCl3 phases.