Strong Coupling of Plasmonic Nanorods with a MoSe₂ Monolayer in the Near-Infrared Shortwave Region

Strong room-temperature light-matter coupling between quantum emitters and plasmonic nanoparticles is a central issue in nanophotonics. However, few studies have reported on the coherent states in the near-infrared shortwave region (NIR-I). In this study, a hybrid system composed of a single gold nanorod (Au NR) and a MoSe2 monolayer was constructed. By tuning the length-to-diameter ratio of the single-anisotropy Au NR to match the exciton energy of MoSe2 at 1.57 eV (791 nm), Rabi splitting of up to 75 meV was obtained via the dark-field scattering spectrum. Moreover, theoretical calculations using the finite-difference time-domain method were obtained and found to correspond with the experimental spectral results. This is attributed to the mode volume reduction and localized electric field distribution at the NIR-I resonance peak. These results facilitate obtaining and manipulating strong room-temperature light-matter couplings in the NIR-I region.