Ultrafast relaxation dynamics of optically excited electrons in Ni
نویسندگان
چکیده
Photon-induced ultrafast energy dissipation in small isolated Ni3 2 has been studied by two-color pumpprobe photoelectron spectroscopy. The time-resolved photoelectron spectra clearly trace the path from a singleelectron excitation to a thermalized cluster via both inelastic electron-electron scattering and electronvibrational coupling. The relatively short electron-electron-scattering time of 215 fs results from the narrow energy spread of the partially filled d levels in this transition-metal cluster. The relaxation dynamics is discussed in view of the cluster size and in comparison to the totally different relaxation behavior of s/p-metal clusters.
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