Coherent Phonons in van der Waals MoSe₂/WSe₂ Heterobilayers.

ABSTRACT: The increasing role of two-dimensional (2D) devices requires the development of new techniques for ultrafast control of physical properties in 2D van der Waals (vdW) nanolayers. A special feature of heterobilayers assembled from vdW monolayers is femtosecond separation of photoexcited electrons and holes between the neighboring layers, resulting in the formation of Coulomb force. Using laser pulses, we generate a 0.8 THz coherent breathing mode in MoSe₂/WSe₂ heterobilayers, which modulates the thickness of the heterobilayer and should modulate the photogenerated electric field in the vdW gap. While the phonon frequency and decay time are independent of the stacking angle between the MoSe₂ and WSe₂ monolayers, the amplitude decreases at intermedia

SUBMITTER: Li C 

PROVIDER: S-EPMC10510584 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature