Revealing localized excitons in WSe2/β-Ga2O3

Cavalini, Camila; Rabahi, Cesar; de Brito, Caique S.; Lee, Eunji; Toledo, José R.; Cazetta, Felipe F.; Fernandes de Oliveira, Raphael B.; Andrade, Marcelo B.; Henini, Mohamed; Zhang, Yuhao; Kim, Jeongyong; Barcelos, Ingrid D.; Galvão Gobato, Yara

Abstract

We have investigated the optical and magneto-optical properties of monolayer (ML) WSe2 on flakes of β-Ga2O3 under high magnetic fields. Remarkably, sharp emission peaks were observed and associated with localized excitons related to point defects. A detailed study of low-temperature photoluminescence (PL) and magneto-PL under high perpendicular magnetic field up to 9 T was carried out. Several sharp emission peaks have shown valley g-factors values close to −4, which is an unusual result for localized excitons in WSe2. Furthermore, some PL peaks have shown higher g-factor values of ≈−7 and ≈−12, which were associated with the hybridization of strain localized dark excitons and defects. The reported results suggest that β-Ga2O3 is, indeed, a promising dielectric substrate for ML WSe2 and also to explore fundamental physics in view of possible applications in quantum information technology.

Citation

Cavalini, C., Rabahi, C., de Brito, C. S., Lee, E., Toledo, J. R., Cazetta, F. F., Fernandes de Oliveira, R. B., Andrade, M. B., Henini, M., Zhang, Y., Kim, J., Barcelos, I. D., & Galvão Gobato, Y. (2024). Revealing localized excitons in WSe2/β-Ga2O3. Applied Physics Letters, 124(14), Article 142104. https://doi.org/10.1063/5.0203628

• Journal Article Type: Article
• Acceptance Date: Mar 15, 2024
• Online Publication Date: Apr 1, 2024
• Publication Date: Apr 1, 2024
• Deposit Date: Apr 7, 2024
• Publicly Available Date: Apr 8, 2024
• Journal: Applied Physics Letters
• Print ISSN: 0003-6951
• Electronic ISSN: 1077-3118
• Publisher: American Institute of Physics
• Peer Reviewed: Peer Reviewed
• Volume: 124
• Issue: 14
• Article Number: 142104
• DOI: https://doi.org/10.1063/5.0203628
• Keywords: Excitons, Optoelectronics, Heterostructures, Fundamental physics, Information technology, 2D materials, Zeeman effect, Oxides, Crystallographic defects, Photoluminescence spectroscopy
• Public URL: https://nottingham-repository.worktribe.com/output/33293448