Figure 2. Resonantly enhanced hot-luminescence in plasmonic silicon.

a, Room-temperature photoluminescence spectrum from a single silicon nanowire coupled with Ω-shaped plasmon nanocavity (d = 70 nm). The calculated frequency-dependent electromagnetic field intensity inside the cavity reproduces the resonances correctly. b to d, Calculated electric field profile at cavity resonance energies of 2.505 eV (b), 2.342 eV (c), and (d) 2.179 eV labeled as A, B, and C on the spectrum, showing the formation of plasmonic cavity modes. The corresponding magnetic field intensities of the cavity modes are provided in the Supplementary Figure S3. The white outlines refer to the Si-SiO₂-Ag interfaces of the Ω-shaped cavity structure.