Ten-valley excitonic complexes in charge-tunable monolayer WSe2
Excitons dominate the optical response of two-dimensional (2D) semiconductors. Strong interactions produce peculiar excitonic complexes, which provide a testing ground for exciton and quantum many-body theories. Here, we report a hitherto unobserved many-body exciton that emerges upon filling both the K and Q valleys of WSe<sub>2</sub>. We optically probe the exciton landscape using charge-tunable devices with unusually thin dielectrics that facilitate doping up to several 10<sup>13</sup> cm<sup>-2</sup>. We observe the emergence of the thermodynamically stable complex when 10 valleys are electrostatically filled. We gain insight into its physics using magneto-optical measurements. Our results are well-described by a model where the number of distinguishable Fermi seas interacting with the photoexcited electron-hole pair defines the complex's behavior. In addition to expanding the repertoire of excitons in 2D semiconductors, this complex could probe the limit of exciton models and answer open questions about screened Coulomb interactions in 2D semiconductors.
Authors
- Amine Ben Mhenni (ORCID: https://orcid.org/0009-0006-2976-3468)
- Hanan Dery (ORCID: https://orcid.org/0000-0002-2640-4068)
- L. Steiner (ORCID: https://orcid.org/0000-0002-9784-3957)
- Takashi Taniguchi (ORCID: https://orcid.org/0000-0002-1467-3105)
- Kenji Watanabe (ORCID: https://orcid.org/0000-0003-3701-8119)
- Jonathan J. Finley (ORCID: https://orcid.org/0000-0003-3036-529X)
- Dinh Van Tuan (ORCID: https://orcid.org/0000-0002-9605-2686)
- Nathan P. Wilson (ORCID: https://orcid.org/0000-0003-2996-122X)
- Alain Dijkstra (ORCID: https://orcid.org/0000-0003-2661-5460)
- Matteo Barbone (ORCID: https://orcid.org/0000-0003-3553-7281)
- Junghwan Kim (ORCID: https://orcid.org/0009-0002-8412-7684)
- Elif Çetiner (ORCID: https://orcid.org/0009-0003-3733-8056)
- Muriel Schur-Wilkens
Institutions
- Schott (Germany) (DE)
- National Institute for Materials Science (JP)
- Munich Center for Quantum Science and Technology (DE)
- University of Rochester (US)
- Technical University of Munich (DE)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-11-05
- DOI
- https://doi.org/10.1038/s41467-025-65731-x
- Citations
- 1
- Primary Topic
- 2D Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 0.52
Funders
- U.S. Department of Energy
- University of Rochester
- International Max Planck Research School for Environmental, Cellular and Molecular Microbiology
- European Commission
- Deutsche Forschungsgemeinschaft
- Ministry of Education, Culture, Sports, Science and Technology
- International Max Planck Research School for Advanced Methods in Process and Systems Engineering
- Munich Center for Quantum Science and Technology
- International Max Planck Research School for Quantum Science and Technology
- Japan Society for the Promotion of Science
- Basic Energy Sciences
- Division of Materials Sciences and Engineering