Dense network of one-dimensional mid-gap metallic modes in monolayer MoSe2 and their spatial undulations

TL;DR

This paper reports the discovery of a dense network of one-dimensional metallic modes at domain boundaries in monolayer MoSe2, with spatial undulations influenced by moire patterns and quantum effects, offering potential for catalysis and novel transport phenomena.

Contribution

It presents the first observation of a dense 1D metallic network in monolayer MoSe2 and analyzes their spatial undulations and potential applications.

Findings

Identification of mid-gap 1D metallic modes at domain boundaries.

Observation of intensity undulations due to moire patterns and quantum effects.

Potential for heterocatalysis and unique transport behaviors.

Abstract

We report the observation of a dense triangular network of one-dimensional (1D) metallic modes in a continuous and uniform monolayer of MoSe2 grown by molecular-beam epitaxy. High-resolution transmission electron microscopy and scanning tunneling microscopy and spectroscopy (STM/STS) studies show these 1D modes are mid-gap states at inversion domain boundaries. STM/STS measurements further reveal intensity undulations of the metallic modes, presumably arising from the superlattice potentials due to moire pattern and the quantum confinement effect. A dense network of the metallic modes with high density of states is of great potential for heterocatalysis applications. The interconnection of such mid-gap 1D conducting channels may also imply new transport behaviors distinct from the 2D bulk.