Related Experiment Video
Updated: Dec 16, 2025

Low-energy Cathodoluminescence for OxyNitride Phosphors
Published on: November 15, 2016
Giant excitonic absorption and emission in two-dimensional group-III nitrides
Maria Stella Prete1, Davide Grassano2, Olivia Pulci1
1Dipartimento di Fisica, Università di Roma Tor Vergata, INFN, Via della Ricerca Scientifica 1, 00133, Rome, Italy.
Abstract:
Absorption and emission of pristine-like semiconducting monolayers of BN, AlN, GaN, and InN are systematically studied by ab-initio methods. We calculate the absorption spectra for in-plane and out-of-plane light polarization including quasiparticle and excitonic effects. Chemical trends with the cation of the absorption edge and the exciton binding are discussed in terms of the band structures. Exciton binding energies and localization radii are explained within the Rytova-Keldysh model for excitons in two dimensions. The strong excitonic effects are due to the interplay of low dimensionality, confinement effects, and reduced screening. We find exciton radiative lifetimes ranging from tenths of picoseconds (BN) to tenths of nanoseconds (InN) at room temperature, thus making 2D nitrides, especially InN, promising materials for light-emitting diodes and high-performance solar cells.
Related Concept Videos
IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations
Ionic Bonding and Electron Transfer
Energy Bands in Solids
Band Formation:
When atoms are brought close together, as in a solid, these discrete energy levels begin to split due to the overlap of electron orbitals from adjacent atoms. This split occurs because of the Pauli exclusion principle, which states...
Two-Dimensional (2D) NMR: Overview
The first step is the preparation period, during which nucleus A is excited with a radiofrequency pulse....
IR Absorption Frequency: Delocalization
In IR...
UV–Vis Spectroscopy: Molecular Electronic Transitions

