DIRECT OBSERVATION OF THE DYNAMICS OF EXCITED ELECTRONIC STATES IN SOLIDS - F-SEC TIME-RESOLVED PHOTOEMISSION OF C-60

Using femtosecond laser pulses in a pump-probe configuration we have s tudied the dynamics of optically excited states in C-60 films deposite d onto a metallic substrate. The excited electrons are observed direct ly by taking photoemission spectra while varying the time-delay betwee n pump and probe pulses. The initially excited electronic configuratio ns which are reached from the ground state via dipole transitions deca y with different time constants into lower energy configurations. (C) 1998 Elsevier Science Ltd.