Photocarrier dynamics in C60: studies of transient photoconductivity and transient photoinduced absorption

The intrinsic dynamics of photoexcited carriers in oxygen-free C60 film and their remarkable evolution as the film is exposed to oxygen are revealed by transient photoconductivity (PC) and transient photoinduced absorption (PA) measurements at various temperatures, light intensities and photon energies. These studies reveal the carrier transport and carrier recombination mechanisms, and provide an estimate for the initial mobility in pristine C60 film; these measurements also demonstrate that exposure C60 film to oxygen creates deep traps that localize the photocarriers and effectively quenches the long-lived multiple trapping transport mechanism.