Abstract
We report ultrafast pump-probe measurements on a graphene/MoS2 heterostructure and demonstrate sub picosecond exciton dissociation and charge transfer from MoS2 to graphene, one order of magnitude faster than in type II two-dimensional heterostructures [1]. The process can be controlled by applying an external gate and shifting the Fermi level of graphene. For pump-probe measurements we excite the gate controlled graphene/MoS2 heterostructure at 400 nm, well above the MoS2 bandgap [2], and probe the normalized differential transmission changes (ΔT/T) of the MoS2 first exciton (A exciton) at 660nm with time resolution~200fs. In this configuration, MoS2 acts as the absorbing material for visible wavelengths while graphene is the electron scavenger [3], as depicted in Fig. 1.
© 2017 IEEE
PDF ArticleMore Like This
Zhen Xu, Zhe Liu, Zhaohui Zhong, and Theodore B. Norris
FF3B.8 CLEO: QELS_Fundamental Science (CLEO:FS) 2020
Riyanka Karmakar, Dipankar Sen, Dipendranath Mandal, and K.V. Adarsh
JW1A.100 CLEO: Applications and Technology (CLEO:A&T) 2021
Yang Yu, Xiao Xing, Wenjie Zhang, Weimin Liu, and Guohong Ma
Tu3B.6 International Conference on Ultrafast Phenomena (UP) 2020