Crystal polarity discrimination for GaN nanowires on graphene

TL;DR

This paper investigates the polarity of GaN nanowires on graphene, combining experimental data with DFT calculations to show that the nanowires are nitrogen-polar due to dipole interactions.

Contribution

It provides the first combined experimental and computational analysis demonstrating nitrogen polarity in GaN nanowires on graphene substrates.

Findings

GaN nanowires on graphene are nitrogen-polar.

DFT analysis confirms N-polar configuration as most stable.

Polarity discrimination is driven by dipole interactions with graphene's π-orbitals.

Abstract

We present experimental data and computational analysis of the formation of GaN nanowires on graphene virtual substrates. We show that GaN nanowires on graphene exhibit nitrogen polarity. We employ the DFT-based computational analysis to demonstrate that among different possible configurations of Ga and N atoms only the N-polar one is stable. We suggest that polarity discrimination occurs due to the dipole interaction between the GaN nanocrystal and $\pi$-orbitals of the graphene sheet.