The functional form of Coulomb interactions in the transition metal dichalcogenides and other van der Waals solids is critical to many of their unique properties, e.g. strongly-correlated electron states, superconductivity and emergent ferromagnetism. This paper presents measurements of key excitonic energy levels in MoSe2/WSe2 heterostructures. These measurements are obtained from resonance Raman experiments on specific Raman peaks only observed at excited states of the excitons. This data is used to validate a model of the Coulomb potential in these structures which predicts the exciton energies to within ~5 meV / 2.5%. This model is used to determine the effect of heterostructure formation on the single-particle band gaps of the layers and will have a wide applicability in designing the next generation of more complex transition metal dichalcogenide structures.
@article{arxiv.2103.09004,
title = {Excited Rydberg States in TMD Heterostructures},
author = {Jacob J. S. Viner and Liam P. McDonnell and David A. Ruiz-Tijerina and Pasqual Rivera and Xiaodong Xu and Vladimir I. Fal'ko and David C. Smith},
journal= {arXiv preprint arXiv:2103.09004},
year = {2021}
}
Comments
19 pages, 3 figures and an additional 14 pages, 7 figures of supplimentary info. Submitted to IOP 2D Materials