Affiliation:
1. Department of Physics Beijing Normal University Beijing 100875 P. R. China
2. Department of Physics Renmin University of China Beijing 100872 P. R. China
3. Beijing Key Laboratory of Energy Conversion and Storage Materials College of Chemistry Beijing Normal University Beijing 100875 China
Abstract
AbstractMoiré superlattices, induced by an angular mismatch in layered materials provide a new index of freedom to manipulate the correlated electron states and many‐body properties of excitons. Here, trilayer MoS2 homostructures with the 3R configuration between the middle (M) and the bottom (B) layer and the top‐to‐middle (T‐M) interlayer twists ranging from 10° to 40° are fabricated via NaCl‐assisted chemical vapor deposition. The twist‐dependent interlayer interactions are systematically investigated by polarized low frequency (PLF) and high frequency (HF) Raman spectroscopy. PLF Raman results show that the energy shift in the shear mode, the breathing modes of LB31 and LB32 is respectively the much in 14°‐ and 28°‐T‐M twisted trilayer, among as‐prepared trilayer MoS2 homostructures. Moreover, the T‐M twist further affects the optical properties of the twisted MoS2 trilayer, evidenced by the photoluminescence (PL) spectroscopy. Moiré excitons are enhanced in the top‐layer twisted MoS2 trilayer with a T‐M twists of 28°, which may originate from the interlayer exciton trapped by the periodical moiré potential. The present work demonstrates that the trilayer homostructures tuned by interlayer twists can be an ideal system to tune the energy band structures and exciton properties for their potential applications in the nano‐optical electronics.
Funder
National Natural Science Foundation of China