Quantum control of population transfer and vibrational states via chirped pulses in four level density matrix equations

We investigate the effect of chirped excitation and the excitation detuning on the coherent control of population transfer and vibrational states in a four-­--level system. Density matrix equations are studied for optimally enhanced processes by considering specific parameters typical of oxazine systems. Our simulations show a strong dependence on the interplay between chirp and excitation detuning and predict enhancement factors up to 3.2 for population transfer and up to 38.5 for vibrational coherences of electronic excited states. The study of the dynamics of the populations and vibrational coherences involved in the four-­--level system allows an interpretation of the different enhancement/suppression processes observed.Peer ReviewedPostprint (published version