Momentum-map-imaging photoelectron spectroscopy of fullerenes with femtosecond laser pulses

摘要: Photoelectron spectra of ${\mathrm{C}}_{60}$ and ${\mathrm{C}}_{70}$, ionized with ultrashort laser pulses, are measured a momentum-map-imaging electron spectrometer. Above the photon energy, 1.6 eV, essentially structureless well described by Boltzmann distributions, temperatures on order ${10}^{4}$ K. This result is similar to previous results for using time-of-flight spectrometer, which confirmed in this study. Comparisons energy distributions recorded identical intensities but different pulse durations demonstrate unambiguously that significant fraction electrons emitted quasithermal processes argue strongly against field ionization or direct multiphoton mechanism. For energies above account about half intensity, whole signal consistent emission.