Plasmonic Nanopyramid Array Enhancing Luminescence of MoS₂ Investigated by Cathodoluminescence

Abstract Transition metal dichalcogenides (TMDs) like molybdenum disulfide (MoS₂) have unique optical properties such as strong luminescence and a tunable bandgap. However, the small interaction distance due to the atomically thin nature of these materials is a limitation for applications. In this study, a significant enhancement of the A‐ and B‐exciton emission in MoS₂ flakes through coupling with plasmonic Au nano‐pyramid arrays fabricated by a colloidal lithography technique is reported. This study experimentally maps local emission enhancement from the structure with a nanometer spatial resolution by cathodoluminescence (CL) technique. Strongly enhanced emission intensity within the MoS₂‐Au pyramids is achieved due to the localized surface plasmon resonance confined in nano‐pyramids and its interaction with the periodicity‐based resonance of the array structure. The results provide an approach to significantly improve the luminescence intensity of MoS₂ through optical interaction with the local plasmonic field, which is promising for applications in optoelectronic devices and nanophotonics.