Coherent vibrational dynamics of polydiacetylenes in their electronic ground stateDedicated to Professor F. Dörr on the occasion of his 80th birthday.

Abstract

The ground state dynamics of linear polymer chains of diacetylenes are investigated by time- and wavenumber-resolved coherent anti-Stokes Raman scattering (CARS). By the femtosecond laser pulses used for the CARS process, different vibrational modes are coherently excited and their evolution is probed on a femtosecond time-scale. By analyzing the dispersed nonlinear signal, the dephasing dynamics can be determined. The phases of the quantum beating between the different coherently excited modes can be used to estimate the onset time of these vibrations.