Efficient light upconversion via resonant exciton-exciton annihilation of dark excitons in few-layer transition metal dichalcogenides
Materials capable of light upconversion-transforming low-energy photons into higher-energy ones-are pivotal in advancing optoelectronics, energy solutions, and photocatalysis. However, the discovery in various materials pays little attention on few-layer transition metal dichalcogenides, primarily due to their indirect bandgaps and weaker light-matter interactions. Here, we report a pronounced light upconversion in few-layer transition metal dichalcogenides through upconversion photoluminescence spectroscopy. Our joint theory-experiment study attributes the upconversion photoluminescence to a resonant exciton-exciton annihilation involving a pair of dark excitons with opposite momenta, followed by the spontaneous emission of upconverted bright excitons, which can have a high upconversion efficiency. Additionally, the upconversion photoluminescence is generic in MoS<sub>2</sub>, MoSe<sub>2</sub>, WS<sub>2</sub>, and WSe<sub>2</sub>, showing a high tuneability from green to ultraviolet light (2.34-3.1 eV). The findings pave the way for further exploration of light upconversion regarding fundamental properties and device applications in two-dimensional semiconductors.
Authors
- Shun‐Jen Cheng (ORCID: https://orcid.org/0000-0002-1721-7914)
- Luke N. Holtzman (ORCID: https://orcid.org/0009-0007-9898-7075)
- James Hone (ORCID: https://orcid.org/0000-0002-8084-3301)
- Madisen Holbrook (ORCID: https://orcid.org/0000-0002-2019-3562)
- Chih‐En Hsu (ORCID: https://orcid.org/0000-0002-9974-8611)
- Chun‐Jui Huang (ORCID: https://orcid.org/0000-0001-7353-3578)
- Jeffrey A. Davis (ORCID: https://orcid.org/0000-0003-4537-4084)
- Ping‐Yuan Lo (ORCID: https://orcid.org/0000-0002-7835-6520)
- Paweł Hawrylak (ORCID: https://orcid.org/0000-0002-4651-3536)
- Katayun Barmak (ORCID: https://orcid.org/0000-0003-0070-158X)
- Michael S. Fuhrer (ORCID: https://orcid.org/0000-0001-6183-2773)
- Shao‐Yu Chen (ORCID: https://orcid.org/0000-0003-3423-9768)
- Hung‐Chung Hsueh (ORCID: https://orcid.org/0000-0003-2830-8771)
- Weihua Wang (ORCID: https://orcid.org/0000-0003-1737-6648)
- Kyle W. Boschen
- Yung-Ning Hsu
- Yi‐Hsun Chen (ORCID: https://orcid.org/0000-0001-6313-5189)
- Guan-Hao Peng (ORCID: https://orcid.org/0000-0002-6611-9579)
Institutions
- Tamkang University (TW)
- Australian Research Council (AU)
- National Yang Ming Chiao Tung University (TW)
- University of Ottawa (CA)
- National Taiwan University (TW)
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (AU)
- Institute of Atomic and Molecular Sciences, Academia Sinica (TW)
- Monash University (AU)
- Swinburne University of Technology (AU)
- National Taiwan Sport University (TW)
- Columbia University (US)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-03-26
- DOI
- https://doi.org/10.1038/s41467-025-57991-4
- Citations
- 3
- Primary Topic
- Perovskite Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 2.19