Epitaxially defined Luttinger liquids on MoS$_2$ bicrystals

TL;DR

This paper reports the epitaxial growth of high-quality MoS2 bicrystals with long mirror twin boundaries, enabling the observation of Luttinger liquid behavior in one-dimensional topological electron systems at room temperature.

Contribution

It introduces a method for growing large, high-quality MoS2 bicrystals with well-defined MTBs, facilitating detailed transport studies of topological 1D electron liquids.

Findings

MTBs exhibit power-law conductance behavior up to room temperature

Atomic-scale defects significantly influence electron transport

Demonstrates a new platform for studying topological Luttinger liquids

Abstract

A mirror twin boundary (MTB) in a transition metal dichalcogenide (TMD) monolayer can host one-dimensional electron liquid of a topological nature with tunable interactions. Unfortunately, the electrical characterization of such boundaries has been challenging due to the paucity of samples with large enough size and high quality. Here, we report an epitaxial growth of monolayer molybdenum disulfide (MoS$_2$) bicrystals with well-isolated MTBs that are tens of micrometers long. Conductance measurements of these MTBs exhibit power-law behaviors as a function of temperature and bias voltage up to room temperature, consistent with electrons tunneling into a Luttinger liquid. Transport measurements of two distinct types of MTBs reveal the critical role of the atomic-scale defects. This study demonstrates that MTBs in TMD monolayers provide an exciting new platform for studying the interplay between electronic interactions and topology.