Figure 24.

(A) SERS spectra recorded on single nantennas via (i) continuous wave excitation (633 nm, 30 μW/μm²) and (ii–iv) pulsed excitation (785 nm, 7 ps, 76 MHz, 100 μW/μm²). In all cases, the polarization of the incident field is aligned with the long axis of the dimer. Micrographs of each dimer, acquired after the SERS measurements, are shown in the insets. (B) Anti-Stokes branch of the electronic Raman scattering (ERS) continuum for continuous wave (cw) (open circles) and pulsed (inset) excitation after removing the molecular lines. The fittings into eq 1 of ref (237) in the text (continuous lines) yield metal electronic temperatures of 385, 3400, 3100, and 2400 K for the spectra shown in panels i–iv, respectively. (C) S-to-AS ratios extracted from the five prominent vibrations of 1,2-di(4-pyridyl)ethylene (BPE) (open circles) and the predicted ratios, assuming equilibration between metal and molecule and using the measured electronic temperature of 385 K (blue trace; see eq 2 of ref (237)). Reproduced with permission from ref (237). Copyright 2018 American Chemical Society.