Quantum-dot states and optical excitations in edge-modulated graphene nanoribbons

TL;DR

This study explores how minimal width modulations in edge-modulated graphene nanoribbons create quantum dots with unique optical properties, offering potential for advanced optoelectronic devices.

Contribution

It provides a first-principles analysis of electronic and optical properties, revealing the formation of tunable quantum dots through edge modulation in graphene nanoribbons.

Findings

Edge modulations induce electron and hole confinement.

Quantum dots exhibit coexisting dot-like and extended excitations.

Optical spectra are highly tunable with minimal width changes.

Abstract

We investigate from first principles the electronic and optical properties of edge-modulated armchair graphene nanoribbons, including both quasi-particle corrections and excitonic effects. Exploiting the oscillating behavior of the ribbon energy gap, we show that minimal width modulations are sufficient to obtain confinement of both electrons and holes, thus forming optically active quantum dots with unique properties, such as cohexistence of dot-like and extended excitations and fine tunability of optical spectra, with great potential for optoelectronic applications.