Fig. 4: Localized surface plasmon resonance and thermal effects.

a Enhanced local EM field around a plasmonic nanoparticle (NP) under resonance conditions. The collective electron oscillations are in phase with the incident light frequency that yields a sharp spectral response. b Absorption and scattering are dominant, respectively, for NPs smaller than 15 nm and larger than 15 nm (Reprinted with permission from¹⁴⁵). c The light-to-heat conversion process of gold nanoparticles (AuNPs) under resonance conditions yields a temperature profile around AuNPs. The profile under femtosecond pulsed illumination has a steep gradient compared to that under continuous wave (CW) illumination (Reprinted with permission from ref. ⁹⁵). d Illustration of LSPR photoexcitation, relaxation of photoexcited LSPR and release of thermal energy to the surrounding medium. The time scale of the energy exchanges is shown on a logarithmic time scale (Reprint permitted under Term of Use from ref. ⁹⁶).