Effective transfer rates for a dissipative two-level system driven by regular and stochastic fields

The transfer processes in a two-level system coupled to a thermal bath and driven by strong regular and stochastic fields are studied. Starting with the master equation for a dissipative quantum system, the derivation of respective kinetic equations and effective transfer rates is demonstrated. For the low-temperature limit and the case of a large value of the reorganization enrgy of the environment it is shown that the action of a strong periodic field can invert the transfer process or block it completely. Applying an additional stochastic field, a weakening of this transfer blocking is obtained.