21 April 2017 Ultrafast charge and energy exchanges at hybrid interfaces involving 2D semiconductors (Conference Presentation)
Author Affiliations +
Two-dimensional transition metal dichalcogenide (2D-TMD) semiconductors are new class of functional materials with a great promise for optoelectronics. Despite their atomic thickness, they strongly interact with light. This allows 2D-TMDs to become suitable converters of photons into useful electric charges in heterostructures involving 2D-TMDs and metallic nano-plasmonics or semiconductor quantum dots (QDs). In this talk, I will illustrate how femtosecond pump-probe spectroscopy can reveal a sub-45 fs charge transfer at a 2D/QDs heterostructure composed of tungsten disulfide monolayers (2D-WS2) and a single layer of cadmium selenide (CdSe)/zinc sulfide (ZnS) core/shell 0D-QDs. In another heterostructure involving 2D-TMDs and plasmonics, I will describe how plasmons of an array of aluminum (Al) nanoantennas are excited indirectly via energy transfer from photoexcited exciton of 2D-WS2 semiconductor. In particular, femtosecond spectroscopy measurements indicated that the lifetime of the resulting plasmon-induced hot electrons in the Al array continue as long as that of the 2D-WS2 excitons. Conversely, the presence of these excited plasmons almost triples the lifetime of the 2D-WS2 excitons from ~15 to ~44 ps. This exciton-plasmon coupling enabled by such hybrid nanostructures may open new opportunities for optoelectronic applications.

This research was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Synthesis of the two-dimensional materials was supported by the Materials Science and Engineering Division, Office of Basic Energy Sciences, U.S. Department of Energy.
Conference Presentation
© (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Abdelaziz Boulesbaa, Kai Wang, Viktoriia E. Babicheva, Ivan I. Kravchenko, Ming-Wei Lin, Masoud Mahjouri-Samani, Mengkun Tian, Alexander A. Puretzky, Ilia N. Ivanov, Christopher M. Rouleau, Bobby G. Sumpter, David B. Geohegan, "Ultrafast charge and energy exchanges at hybrid interfaces involving 2D semiconductors (Conference Presentation)", Proc. SPIE 10093, Synthesis and Photonics of Nanoscale Materials XIV, 1009308 (21 April 2017); doi: 10.1117/12.2253659; https://doi.org/10.1117/12.2253659

Back to Top