Abstract.
Effects of confinement on the electron-electron (e-e) and electron-phonon (e-ph) thermalization dynamics in noble metal clusters are calculated using simple approaches. The model predictions are compared with femtosecond pump-probe measurements which display an acceleration of the e-e and e-ph relaxation dynamics. The size-effects on the e-e relaxation dynamics are consistent with a model involving the surface-induced reduction of the screening efficiency of the Coulomb e-e interaction. With regard to the e-ph relaxation dynamics, this model yields too large time constants, pointing out deficiencies of the standard modelling of the e-ph energy exchanges in bulk metals. Analysis of these deficiencies shows that the bare e-ion interaction has to be involved in the transition matrix element describing the non-adiabatic e-ph energy exchanges.
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Lermé, J., Celep, G., Broyer, M. et al. Effects of confinement on the electron and lattice dynamics in metal nanoparticles. Eur. Phys. J. D 34, 199–204 (2005). https://doi.org/10.1140/epjd/e2005-00107-8
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DOI: https://doi.org/10.1140/epjd/e2005-00107-8