Flows in nonequilibrium quantum systems and quantum photosynthesis
  A three level quantum system interacting with nonequilibrium environment is investigated. The stationary state of the system is found (both for non-coherent and coherent environment) and relaxation and decoherence to the stationary state is described. The stationary state of the system will be non-equilibrium and will generate flows. We describe the dependence of the flows on the state of the environment.   We also discuss application of this model to the problem of quantum photosynthesis, in particular, to description of flows of excitons and generation of excitonic coherences. 
S.V. Kozyrev, A.A. Mironov, A.E. Teretenkov, I.V. Volovich
quant-ph