Weak plasmon-exciton coupling between monolayer molybdenum disulfide and aluminum disks.

ABSTRACT

Manipulation of the photoluminescence (PL) of monolayer (ML) molybdenum disulfide (MoS2) with metallic plasmonic nanostructures has attracted much more attention for potential applications in optoelectronic devices. However, due to the limitation of resonance wavelength and oxidation properties, gold and silver are not the best selections for manipulating PL of MoS2. Here, we employ aluminum (Al) disks to tune the PL of ML MoS2. We have found that PL enhancement reaches the maximum when plasmonic resonances of Al disks overlap with the absorption peaks of ML MoS2. Near-field simulations show that PL enhancement is due to weak plasmon-exciton coupling.