| Autor: |
Stephen Boandoh, Fu-He Hsiao, Bongki Shin, Majvor Mack, Linus P. Grote, Rongbin Wang, Yimo Han, Jun Lou, Norbert Koch, Norbert H. Nickel, Chih-Wei Luo, Yu-Tsung Tsai |
| Jazyk: |
angličtina |
| Rok vydání: |
2022 |
| Předmět: |
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| Zdroj: |
Advanced Photonics Research, Vol 3, Iss 8, Pp n/a-n/a (2022) |
| Druh dokumentu: |
article |
| ISSN: |
2699-9293 |
| DOI: |
10.1002/adpr.202200046 |
| Popis: |
Although microscopic techniques have been used to characterize transition metal dichalcogenides (TMDs), direct observation of charge carrier dynamics distribution in TMDs with diverse shapes remains unexplored. Herein, ultrafast pump–probe microscopy (UPPM) is employed to reveal the carrier dynamics distribution in molybdenum disulfide (MoS2) and tungsten disulfide (WS2) monolayer of four shapes: triangular (t‐MoS2), curved triangular (c‐MoS2), triangular (t‐WS2), and hexagonal (h‐WS2). Monitoring the photon transmission T at 1.55 eV after pumping with a photon energy of 3.1 eV, a negative ΔT/T occurs in t‐MoS2 and c‐MoS2, while a positive ΔT/T is detected in t‐WS2 and h‐WS2 after 3–7 ps time evolution. This distinctive behavior is attributed to deep/shallow defects below the conduction band minimum (CBM) in MoS2 and WS2. Spatial‐independent ΔT/T is observed in t‐MoS2 and t‐WS2, while the ΔT/T in c‐MoS2 has a rapid decay of photoexcited carriers at the vertices and curved edges. Additionally, a threefold symmetry of ΔT/T is revealed in h‐WS2, attributed to the dissimilar occupation of defect states near the h‐WS2 CBM. This work paves the way for examining charge carrier dynamics of various shapes of TMDs and provides a unique microscopic method for studying the charge carrier dynamics in emerging TMDs heterostructures. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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