We present theoretical results for the radiative rates and doping-dependent photoluminescence spectrum of interlayer excitonic complexes localized by donor impurities in MoSe2/WSe2 twisted heterobilayers, supported by quantum Monte Carlo calculations of binding energies and wave-function overlap integrals. For closely aligned layers, radiative decay is made possible by the momentum spread of the localized complexes' wave functions, resulting in few μs−1 radiative rates. For strongly misaligned layers, the short-range interaction between the carriers and impurity provides a finite radiative rate with a strong asymptotic twist angle dependence ∝θ−8. Finally, phonon-assisted recombination is considered, with emission of optical phonons in both layers resulting in additional weaker emission lines, redshifted by the phonon energy.
@article{arxiv.1802.06005,
title = {Localized interlayer complexes in heterobilayer transition metal dichalcogenides},
author = {Mark Danovich and David A. Ruiz-Tijerina and Ryan J. Hunt and Marcin Szyniszewski and Neil D. Drummond and Vladimir I. Fal'ko},
journal= {arXiv preprint arXiv:1802.06005},
year = {2018}
}