Ionization and Fragmentation of C60 via Multiphoton-Multiplasmon Excitation.

We study the intensity dependence of ionization and fragmentation of buckminsterfullerene (C60) in strong laser fields. Our data provide strong evidence that at intensities &1014 Wycm2 these processes occur predominantly via multiphoton excitation of the 20 eV plasmon resonance of C60. At least two plasmons have to be created to initiate fragmentation or multiple ionization. [S0031-9007(96)01124-6]