Active Light Control of the MoS2 Monolayer Exciton Binding Energy.
Plasmonic excitation of Au nanoparticles deposited on a MoS2 monolayer changes the absorption and photoluminescence characteristics of the material. Hot electrons generated from the Au nanoparticles are transferred into the MoS2 monolayers, resulting in n-doping. The doping effect of plasmonic hot electrons modulates the dielectric permittivity of materials, resulting in a red shift of both the absorption and the photoluminescence spectrum. This spectroscopic tuning was further investigated experimentally by using different Au nanoparticle concentrations, excitation laser wavelengths, and intensities. An analytical model for the photoinduced modulation of the MoS2 dielectric function and its exciton binding energy change is developed and used to estimate the doping density of plasmonic hot electrons. Our approach is important for the development of photonic devices for active control of light by light.
School of Physics, State Key Lab for Mesoscopic Physics, Academy for Advanced Interdisciplinary Studies, Peking University , Beijing 100871, China.
Ziwei
Z
Li
School of Physics, State Key Lab for Mesoscopic Physics, Academy for Advanced Interdisciplinary Studies, Peking University , Beijing 100871, China.
Yingdong
Y
Xiao
Yongji
Y
Gong
School of Physics, State Key Lab for Mesoscopic Physics, Academy for Advanced Interdisciplinary Studies, Peking University , Beijing 100871, China.
Zongpeng
Z
Wang
School of Physics, State Key Lab for Mesoscopic Physics, Academy for Advanced Interdisciplinary Studies, Peking University , Beijing 100871, China.
Yimin
Y
Kang
School of Physics, State Key Lab for Mesoscopic Physics, Academy for Advanced Interdisciplinary Studies, Peking University , Beijing 100871, China.
Shuai
S
Zu
Pulickel M
PM
Ajayan
Peter
P
Nordlander
School of Physics, State Key Lab for Mesoscopic Physics, Academy for Advanced Interdisciplinary Studies, Peking University , Beijing 100871, China.
Zheyu
Z
Fang
MoS2; absorption; active tuning; exciton; plasmonic hot electron