Radiative lifetime of free excitons in hexagonal boron nitride

Hexagonal boron-nitride nanomesh magnets

Excitons in boron nitride nanotubes: dimensionality effects.

We show that the optical absorption spectra of boron nitride (BN) nanotubes are dominated by strongly bound excitons. Our first-principles calculations indicate that the binding energy for the first and dominant excitonic peak depends sensitively on the dimensionality of the system, varying from 0.7 eV in bulk hexagonal BN via 2.1 eV in the single sheet of BN to more than 3 eV in the hypothetic...

Radiative lifetime of excitons in carbon nanotubes.

We calculate the radiative lifetime and energy bandstructure of excitons in semiconducting carbon nanotubes within a tight-binding approach including the electron-hole correlations via the Bethe-Salpeter equation. In the limit of rapid interband thermalization, the radiative decay rate is maximized at intermediate temperatures and decreases at low temperature because the lowest-energy excitons ...

Excitons in van der Waals materials: from monolayer to bulk hexagonal boron nitride

Jaakko Koskelo, Giorgia Fugallo, 3 Mikko Hakala, Matteo Gatti, 3, 4 Francesco Sottile, 3 and Pierluigi Cudazzo 3 Department of Physics, P.O. Box 64, FI-00014 University of Helsinki, Helsinki, Finland Laboratoire des Solides Irradiés, École Polytechnique, CNRS, CEA, Université Paris-Saclay, F-91128 Palaiseau, France European Theoretical Spectroscopy Facility (ETSF) Synchrotron SOLEIL, L’Orme des...

Optoelectronic Properties and Excitons in Hybridized Boron Nitride and Graphene Hexagonal Monolayers

We explain the nature of the electronic band gap and optical absorption spectrum of Carbon Boron Nitride (CBN) hybridized monolayers using density functional theory (DFT), GW and Bethe-Salpeter equation calculations. The CBN optoelectronic properties result from the overall monolayer bandstructure, whose quasiparticle states are controlled by the C domain size and lie at separate energy for C a...