Interlayer excitons in MoSe2/WSe2 heterostructures from first principles

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Details zur Publikation

Autorinnen und Autoren: Gillen R, Maultzsch J
Zeitschrift: Physical Review B
Verlag: AMER PHYSICAL SOC
Jahr der Veröffentlichung: 2018
Band: 97
Heftnummer: 16
ISSN: 2469-9950
Sprache: Englisch


Abstract

Based on ab initio theoretical calculations of the optical spectra of vertical heterostructures of MoSe2 (or MoS2) and WSe2 sheets, we reveal two spin-orbit-split Rydberg series of excitonic states below the A excitons of MoSe2 and WSe2 with a significant binding energy on the order of 250 meV for the first excitons in the series. At the same time, we predict from accurate many-body G(0)W(0) calculations that crystallographically aligned MoSe2/WSe2 heterostructures exhibit an indirect fundamental band gap. Due to the type-II nature of the MoSe2/WSe2 heterostructure, the indirect transition and the exciton Rydberg series corresponding to a direct transition exhibit a distinct interlayer nature with spatial charge separation of the coupled electrons and holes. Our calculations confirm the recent experimental observation of a doublet nature of the long-lived states in photoluminescence spectra of MoX2/WY2 heterostructures, and we attribute these two contributions to momentum-direct interlayer excitons at the K point of the hexagonal Brillouin zone and to momentum-indirect excitons at the indirect fundamental band gap. Our calculations further suggest a noticeable effect of stacking order on the electronic band gaps and on the peak energies of the interlayer excitons and their oscillation strengths.


FAU-Autorinnen und Autoren / FAU-Herausgeberinnen und Herausgeber

Gillen, Roland
Lehrstuhl für Experimentalphysik
Maultzsch, Janina Prof. Dr.
Lehrstuhl für Experimentalphysik


Forschungsbereiche

Layered materials
Lehrstuhl für Experimentalphysik


Zitierweisen

APA:
Gillen, R., & Maultzsch, J. (2018). Interlayer excitons in MoSe2/WSe2 heterostructures from first principles. Physical Review B, 97(16). https://dx.doi.org/10.1103/PhysRevB.97.165306

MLA:
Gillen, Roland, and Janina Maultzsch. "Interlayer excitons in MoSe2/WSe2 heterostructures from first principles." Physical Review B 97.16 (2018).

BibTeX: 

Zuletzt aktualisiert 2019-18-03 um 10:03