Open AccessEffect of interlayer interactions on exciton luminescence in atomic-layered MoS2 crystals
Author(s) -
Jung Gon Kim,
Won Seok Yun,
Sunghwan Jo,
JaeDong Lee,
ChangHee Cho
Publication year - 2016
Publication title -
scientific reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.24
H-Index - 213
ISSN - 2045-2322
DOI - 10.1038/srep29813
Subject(s) - exciton , photoluminescence , materials science , luminescence , redistribution (election) , band bending , condensed matter physics , transition metal , quantum confined stark effect , electric field , chemical physics , molecular physics , optoelectronics , stark effect , chemistry , physics , quantum mechanics , biochemistry , politics , political science , law , catalysis
The atomic-layered semiconducting materials of transition metal dichalcogenides are considered effective light sources with both potential applications in thin and flexible optoelectronics and novel functionalities. In spite of the great interest in optoelectronic properties of two-dimensional transition metal dichalcogenides, the excitonic properties still need to be addressed, specifically in terms of the interlayer interactions. Here, we report the distinct behavior of the A and B excitons in the presence of interlayer interactions of layered MoS 2 crystals. Micro-photoluminescence spectroscopic studies reveal that on the interlayer interactions in double layer MoS 2 crystals, the emission quantum yield of the A exciton is drastically changed, whereas that of the B exciton remains nearly constant for both single and double layer MoS 2 crystals. First-principles density functional theory calculations confirm that a significant charge redistribution occurs in the double layer MoS 2 due to the interlayer interactions producing a local electric field at the interfacial region. Analogous to the quantum-confined Stark effect, we suggest that the distinct behavior of the A and B excitons can be explained by a simplified band-bending model.