Details

Autor(en) / Beteiligte

• Bian, Ang
• Fu, Shaohua
• Wang, Pengzhi
• Zhao, Kun
• He, Jiaqi
• Zhang, Xiaoxian
• He, Dawei
• Wang, Yongsheng
• Zhao, Hui

Titel

Ultrafast charge transfer and carrier dynamics in a WS2/MoSe2 few-layer van der Waals heterostructure

Ist Teil von

• Journal of materials chemistry. C, Materials for optical and electronic devices, 2022-02, Vol.10 (13), p.5328-5335

Ort / Verlag

Cambridge: Royal Society of Chemistry

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Photocarrier dynamics including interlayer charge transfer and intralayer valley scattering are studied in a heterostructure formed by trilayer WS2 and MoSe2. The sample is fabricated by mechanical exfoliation and dry transfer and characterized by atomic force microscopy, Raman spectroscopy, and photoluminescence measurements. The conduction band minima of the two materials are nearly degenerate, representing a unique band alignment. Layer-selective pump–probe measurements are performed with three configurations to reveal a complete picture of the photocarrier dynamics. By comparing the heterostructure with the two individual trilayer materials in each experimental configuration, ultrafast interlayer charge transfer is unambiguously observed, which occurs on the same time scale as the intralayer valley scattering of the photocarriers. The quasi-equilibrium distribution of electrons in the two layers mediate the fast carrier recombination process. These results show that the band structures of the few-layer transition metal dichalcogenides can enable rich photocarrier dynamics with intermediate band alignments that are complementary to the previously studied monolayer–monolayer heterostructures.