Electrical control of excitons in van der Waals heterostructures with type-II band alignment

A. Chaves, J. G. Azadani, V. Ongun Özçelik, R. Grassi, T. Low

Research output: Contribution to journalArticlepeer-review

22 Scopus citations

Abstract

We investigate excitons in stacked transition-metal dichalcogenide layers under a perpendicularly applied electric field, herein MoSe2/WSe2 van der Waals heterostructures (vdWHs). Band structures are obtained with density functional theory (DFT), along with electron and hole wave functions in conduction and valence bands, respectively. A minimal continuum model, parametrized by the DFT results, is presented, allowing for the calculation of the excitonic states. Although the type-II nature of the heterostructure leads to a fully charge separated interlayer exciton on the ground states, our results show that moderate values of electric field produce more evenly distributed wave functions along the vdWH, namely, hybrid inter/intralayer exciton states, where both the interlayer exciton binding energy and, most notably, its oscillator strength are enhanced.

Original languageEnglish (US)
Article number121302
JournalPhysical Review B
Volume98
Issue number12
DOIs
StatePublished - Sep 12 2018

Bibliographical note

Funding Information:
Acknowledgments. Discussions with J. Kunstman, D. R. Reichman, and C. W. Wong are gratefully acknowledged. A.C. has been financially supported by CNPq, through the PRONEX/FUNCAP and PQ programs. J.A. and T.L. acknowledge support from NSF ECCS-1542202. We acknowledge computational support from the Minnesota Supercomputing Institute (MSI).

Publisher Copyright:
© 2018 American Physical Society.

Fingerprint

Dive into the research topics of 'Electrical control of excitons in van der Waals heterostructures with type-II band alignment'. Together they form a unique fingerprint.

Cite this