Pump-probe spectra and nuclear dynamics for a dissipative molecular system in a strong laser field: predissociation dynamics

The predissociation dynamics of a molecular system under a strong laser field in the condensed phase is investigated by direct numerical integration of the multi-state quantum Fokker-Planck equation. Numerical calculations of probe absorption spectra driven by a strong pump pulse are presented, and discussed. The results show dynamical Stark splitting, but, in contrast to the Bloch equations which contain an infinite-temperature dephasing, we find that at finite temperatures their peaks have different heights even when the pump pulse is on resonance. Furthermore we observe the effect of the diabatic coupling between excited and dissociative states as the peaks on the spectra.