▎ 摘　　要

Fully understanding the properties of plasmonic nanocavity would boost the spectral detection technolo-gies based on plasmons. Recent efforts are mainly focused on the light-matter interactions, which greatly facilities the cognition for nano-optics in the hot spot. However, realizing the high spatial resolution of vertical plasmons in the specific plasmonic nanocavity has been elusive to date. Herein, the monolayer graphene-mediated plasmonic nanocavity has been constructed, which proves the nanoscale in-homogeneity of the enhanced electromagnetic field distribution. Via sandwiching the graphene monolayer at various positions insider fixed nanocavity, we also successfully and quantitatively elucidate the spatial-dependent resonance of the cavity plasmon mode with a resonance spectral shifts down to ca. 4.43 Angstrom/nm. Simultaneously, the experimental results and theoretical calculation illustrate the correla-tion between the near field and far field in the hot spot, which also provides a novel strategy for manip-ulating the light-matter interactions at the nanoscale and graphene nano-devices fabrication based on plasmons.(c) 2022 Elsevier Ltd. All rights reserved.