Femtosecond pulse dependence of dissipation in molecular systems

Externally applied optical fields may influence molecular dynamics in a direct way alternating the reversible part of the dynamics but also in an indirect manner changing the dissipative processes. This indirect field influence is studied in the framework of the quantum master equation for the density matrix including a field-dependent Redfield tensor. Within a simple model appropriate to describe a dye molecule in solution, the field influence on molecular dynamics is studied for different laser-pulse intensities and lengths as well as bath correlation times. The possible external field control of dissipation is underlined.