Understanding relaxation dynamics in structurally precise metal clusters using 2DES

Two- and Three-dimensional electronic spectroscopy (2DES and 3DES) was used to study electronic energy relaxation in colloidal metal nanoparticle ensembles. Following plasmon excitation, these systems dissipate energy by sequential plasmon dephasing, “hot” electron-electron scattering, electron-phonon scattering and energy transfer to the environment. Using plasmon-resonant 2DES, hot electron dynamics were distinguished from thermalized carrier cooling in plasmonic nanorods. Polarization-dependent 2DES was used to study the importance of electronic state symmetry in carrier relaxation processes. Finally, 3DES was used to resolve electronic-state and phonon-mode-specific electron-phonon scattering.