Hybridized Plasmons in Au Nanowire Dimers Enable Polarization-Selective Exciton Modulation and Hot-Electron Injection...

Hybridized plasmon modes in coupled metal nanostructures offer unique opportunities to tailor light-matter interactions and interfacial charge transfer at the nanoscale, surpassing the capabilities of isolated plasmonic elements. In this work, we compare the optical and electrical characteristics of MoS₂ monolayers integrated with single Au nanowires (S-NWs) and Au nanowire dimers (D-NWs). While S-NW supports a transverse plasmonic resonance at ∼500 nm, D-NW exhibits an additional hybridized plasmon resonance at ∼650 nm originated from strong near-field coupling. This hybridized mode leads to significantly enhanced polarization-selective photoluminescence in MoS₂/D-NW integrated systems, accompanied by pronounced modulation of the exciton-to-trion population ratio. Furthermore, polarization- and wavelength-dependent Kelvin probe force microscopy directly visualizes nanoscale surface potential changes, providing real-space evidence of plasmon-mediated hot-electron injection from D-NW into MoS₂ at the contact regions. These results demonstrate that D-NWs enable enhanced and tunable plasmon-exciton-charge interactions, establishing TMD/D-NW architectures as a versatile platform for high-performance optoelectronic devices.