Figure 4.

Remote-excitation of molecules in nanocavities using delocalized plasmon modes in a μ-resonator. (a) Simulated electric-field confinement in the gap for 0.8 NA Gaussian excitation onto the disk edge. The red dashed line shows the excitation wavelength (633 nm, 2 mW μm⁻²). (b) Optical setup for remote excitation of molecules in nanocavities. Laser light is blocked by two notch filters (NFs) placed before CMOS camera. (c, d) SERS images from NPoR when laser light excites (c) the nanoparticle directly or (d) the disk edge. Excitation points are marked with red arrows.