Charge-tuneable biexciton complexes in monolayer WSe2

• DOI: 10.1038/s41467-018-05632-4
• Publication Date: 2018-09-07T10:34:23Z
• Authors: Matteo Barbone; Alejandro R.-P. M...; Dhiren M. Kara; Carmen Palacios-B...; Alisson R. Cadore; Domenico De Fazio; Benjamin Pingault; Elaheh Mostaani; Han Li; Bin Chen; Kenji Watanabe; Takashi Taniguchi; Sefaattin Tongay; Gang Wang; Andrea C. Ferrari; Mete Atatüre
• Keywords: Biexciton; Tungsten diselenide

Monolayer transition metal dichalcogenides have strong Coulomb-mediated many-body interactions. Theoretical studies predicted the existence of numerous multi-particle excitonic states. Two-particle excitons and three-particle trions been identified by their optical signatures. However, more complex states such as biexcitons elusive due to limited spectral quality emission. Here, we report direct evidence two biexciton complexes in monolayer tungsten diselenide: four-particle neutral five-particle negatively charged biexciton. We distinguish these power-dependent photoluminescence demonstrate full electrical switching between them. determine band elementary particles comprising through magneto-optical spectroscopy. also resolve a splitting 2.5 meV for biexciton, which attribute fine structure, providing reference subsequent studies. Our results unveil nature multi-exciton transitionmetal offer routes towards deterministic control quantum phenomena.