The optical response of artificially twisted MoS $$_2$$ 2 bilayers

Abstract Two-dimensional layered materials offer the possibility to create artificial vertically stacked structures possessing an additional degree of freedom—the interlayer twist. We present a comprehensive optical study of artificially stacked bilayers (BLs) MoS $$_2$$ 2 encapsulated in hexagonal...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: M. Grzeszczyk, J. Szpakowski, A. O. Slobodeniuk, T. Kazimierczuk, M. Bhatnagar, T. Taniguchi, K. Watanabe, P. Kossacki, M. Potemski, A. Babiński, M. R. Molas
Formato: article
Lenguaje:EN
Publicado: Nature Portfolio 2021
Materias:
R
Q
Acceso en línea:https://doaj.org/article/e499ff474f2344728f976e456bd37ad9
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Descripción
Sumario:Abstract Two-dimensional layered materials offer the possibility to create artificial vertically stacked structures possessing an additional degree of freedom—the interlayer twist. We present a comprehensive optical study of artificially stacked bilayers (BLs) MoS $$_2$$ 2 encapsulated in hexagonal BN with interlayer twist angle ranging from 0 $$^{\circ }$$ ∘ to 60 $$^{\circ }$$ ∘ using Raman scattering and photoluminescence spectroscopies. It is found that the strength of the interlayer coupling in the studied BLs can be estimated using the energy dependence of indirect emission versus the A $$_\text {1g}$$ 1g –E $$_\text {2g}^1$$ 2g 1 energy separation. Due to the hybridization of electronic states in the valence band, the emission line related to the interlayer exciton is apparent in both the natural (2H) and artificial (62 $$^\circ $$ ∘ ) MoS $$_2$$ 2 BLs, while it is absent in the structures with other twist angles. The interlayer coupling energy is estimated to be of about 50 meV. The effect of temperature on energies and intensities of the direct and indirect emission lines in MoS $$_2$$ 2 BLs is also quantified.