Incommensurate double-walled carbon nanotubes as one-dimensional moir\'e crystals

TL;DR

This paper demonstrates that moiré patterns in incommensurate double-walled carbon nanotubes critically influence their electronic properties, enabling classification of these nanowires as one-dimensional moiré crystals with diverse electronic behaviors.

Contribution

It introduces the concept of incommensurate double-walled carbon nanotubes as one-dimensional moiré crystals, linking their atomic lattice misalignments to electronic structure variations.

Findings

Electronic properties vary from metallic to insulating depending on moiré patterns.

Moiré patterns determine the electronic states in incommensurate nanotubes.

Even similar semiconducting nanotubes exhibit different electronic behaviors due to moiré effects.

Abstract

Cylindrical multishell structure is one of the prevalent atomic arrangements in nanowires. Being multishell, the well-defined atomic periodicity is hardly realized in it because the periodic units of individual shells therein generally do not match except for very few cases, posing a challenge to understand its physical properties. Here we show that moir\'e patterns generated by superimposing atomic lattices of individual shells are decisive in determining its electronic structures. Double- walled carbon nanotubes, as an example, are shown to have spectacular variations in their electronic properties from metallic to semiconducting and further to insulating states depending on their moir\'e patterns, even when they are composed of only semiconducting nanotubes with almost similar energy gaps and diameters. Thus, aperiodic multishell nanowires can be classified into new one-dimensional moir\'e crystals with distinct electronic structures.