Excited state evolution in polydiacetylene studied by sub-10-fs time resolved spectroscopy

Solutions of polycarbazolyldiacetylene in benzene were studied using ultrabroadband sub-10-fs excitation pulses obtained from a visible optical parametric amplifier. The semiconducting polymers exhibited a steep onset of ground state absorption. The differential transmission signal was observed to be dependent on pump-probe delay at the probe wavelength of 590 nm