Ultrahigh-Purity Single-Photon Emission from 2D WSe<sub>2</sub> via Effective Suppression of Classical Emission
Single-photon emitters (SPEs) in two-dimensional WSe<sub>2</sub> offer high extraction efficiency and on-chip compatibility, but achieving high purity remains challenging. We present two strategies to suppress classical emission and enhance purity in WSe<sub>2</sub>-based SPEs. In monolayer WSe<sub>2</sub>, we exploited the presence and absence of valley-spin locking in free and bound excitons, respectively, to achieve purity of 98.3% via polarization control and 99.0% combined with near-resonant excitation. In bilayer WSe<sub>2</sub>, we obtained 97.0% purity without polarization filtering, enabled by the indirect band gap and inversion symmetry. These values represent some of the highest as-measured purities reported for 2D TMD SPEs. Our methods do not require complex fabrication or instrumentation and are supported by first-principles calculations of the vacancy state of Se and spin degeneracy. This work offers practical pathways for realizing high-quality single-photon sources for emerging quantum technologies.
Authors
- Luke N. Holtzman (ORCID: https://orcid.org/0009-0007-9898-7075)
- Xuefeng Qian (ORCID: https://orcid.org/0000-0002-8199-6502)
- James Hone (ORCID: https://orcid.org/0000-0002-8084-3301)
- Shengxi Huang (ORCID: https://orcid.org/0000-0002-3618-9074)
- Vasili Perebeinos (ORCID: https://orcid.org/0000-0002-0234-8188)
- James H. Edgar (ORCID: https://orcid.org/0000-0003-0918-5964)
- Wenjing Wu (ORCID: https://orcid.org/0000-0003-0643-7986)
- Kinfung Ngan
- H. Z. Shen (ORCID: https://orcid.org/0000-0002-4017-7367)
- Shuo Sun (ORCID: https://orcid.org/0009-0003-9196-8905)
- Junichiro Kono (ORCID: https://orcid.org/0000-0002-4195-0577)
- Alex Strasser (ORCID: https://orcid.org/0000-0002-6573-0747)
- Song Liu (ORCID: https://orcid.org/0000-0002-3046-3335)
- T. Hoang (ORCID: https://orcid.org/0000-0002-0919-1072)
- Zhongqi Xiu
Institutions
- Joint Institute for Laboratory Astrophysics (US)
- Kansas State University (US)
- Mitchell Institute (US)
- University of Colorado System (US)
- University at Buffalo, State University of New York (US)
- Rice University (US)
- Columbia University (US)
- Texas A&M University (US)
Publication Details
- Journal
- Nano Letters
- Published
- 2025-07-05
- DOI
- https://doi.org/10.1021/acs.nanolett.5c01718
- Citations
- 2
- Primary Topic
- 2D Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 1.04
Funders
- Alfred P. Sloan Foundation
- W. M. Keck Foundation
- Welch Foundation
- Division of Materials Research
- Division of Civil, Mechanical and Manufacturing Innovation
- Division of Electrical, Communications and Cyber Systems
- Air Force Office of Scientific Research