Localization and interaction of interlayer excitons in MoSe2/WSe2 heterobilayers
Journal article, 2023

Transition metal dichalcogenide (TMD) heterobilayers provide a versatile platform to explore unique excitonic physics via the properties of the constituent TMDs and external stimuli. Interlayer excitons (IXs) can form in TMD heterobilayers as delocalized or localized states. However, the localization of IX in different types of potential traps, the emergence of biexcitons in the high-excitation regime, and the impact of potential traps on biexciton formation have remained elusive. In our work, we observe two types of potential traps in a MoSe2/WSe2 heterobilayer, which result in significantly different emission behavior of IXs at different temperatures. We identify the origin of these traps as localized defect states and the moiré potential of the TMD heterobilayer. Furthermore, with strong excitation intensity, a superlinear emission behavior indicates the emergence of interlayer biexcitons, whose formation peaks at a specific temperature. Our work elucidates the different excitation and temperature regimes required for the formation of both localized and delocalized IX and biexcitons and, thus, contributes to a better understanding and application of the rich exciton physics in TMD heterostructures.

Author

Hanlin Fang

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology

Qiaoling Lin

Technical University of Denmark (DTU)

Yi Zhang

Aalto University

J. J.P. Thompson

Philipps University Marburg

Sanshui Xiao

Technical University of Denmark (DTU)

Zhipei Sun

Aalto University

Ermin Malic

Philipps University Marburg

2D-Tech

Saroj Prasad Dash

2D-Tech

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Witlef Wieczorek

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology

Nature Communications

2041-1723 (ISSN) 20411723 (eISSN)

Vol. 14 1 6910

Graphene Core Project 3 (Graphene Flagship)

European Commission (EC) (EC/H2020/881603), 2020-04-01 -- 2023-03-31.

2D material-based technology for industrial applications (2D-TECH)

VINNOVA (2019-00068), 2020-05-01 -- 2024-12-31.

GKN Aerospace Sweden (2D-tech), 2021-01-01 -- 2024-12-31.

Subject Categories

Atom and Molecular Physics and Optics

Condensed Matter Physics

DOI

10.1038/s41467-023-42710-8

PubMed

37903787

More information

Latest update

2/12/2024