# Stacking-dependent electronic structure of trilayer graphene resolved by nanospot angle-resolved photoemission spectroscopy

## TL;DR

This study uses nanospot ARPES to directly observe and distinguish the electronic structures of different stacking orders in trilayer graphene, revealing their unique properties and providing key band parameters.

## Contribution

First direct experimental resolution of electronic structures for all three stacking orders in trilayer graphene using NanoARPES.

## Key findings

- Identified coexistence of three stacking types in trilayer graphene.
- Revealed distinct electronic band structures for each stacking.
- Provided quantitative band parameters for different stackings.

## Abstract

The crystallographic stacking order in multilayer graphene plays an important role in determining its electronic structure. In trilayer graphene, rhombohedral stacking (ABC) is particularly intriguing, exhibiting a flat band with an electric-field tunable band gap. Such electronic structure is distinct from simple hexagonal stacking (AAA) or typical Bernal stacking (ABA), and is promising for nanoscale electronics, optoelectronics applications. So far clean experimental electronic spectra on the first two stackings are missing because the samples are usually too small in size (um or nm scale) to be resolved by conventional angle-resolved photoemission spectroscopy (ARPES). Here by using ARPES with nanospot beam size (NanoARPES), we provide direct experimental evidence for the coexistence of three different stackings of trilayer graphene and reveal their distinctive electronic structures directly. By fitting the experimental data, we provide important experimental band parameters for describing the electronic structure of trilayer graphene with different stackings.