Fig. 4.

(A) Change in the effective temperature relative to room temperature ΔT_eff = T_eff − 300 K of Raman scattering by AuNRs with absorption peak at 787 nm excited by laser pulses of 0.45-ps width. ΔT_eff calculated from the data using Eq. 4 are shown as lines that show some noise. ΔT_eff calculated using Eqs. 4 and 6 with the optical cross-section σ_abs as a fitting parameter are shown as smooth lines. The best fit to the data for −1,500 cm⁻¹ < Δω < 1,500 cm⁻¹ gives σ_abs = 2,700 nm². (B and C) ΔT_eff of the measurement at a Raman shift of (B) −500 cm⁻¹ and (C) 500 cm⁻¹ with laser pulse duration of 0.45 ps (black squares) and 1.3 ps (red circles). The solid lines show the predicted values of ΔT_eff from Eqs. 4 and 6 as a function of laser power using σ_abs = 2,700 nm².