Model of Vibrons in Quantum Photosynthesis as an Analog of a Model of Laser

Abstract

The mechanism of vibronic amplification of transport of excitons has been discussed in connection with quantum photosynthesis. Vibrons (some modes of vibrations of molecules) have been observed experimentally in photosynthetic systems. In the present paper we consider models of vibronic amplification of quantum transfer in which the generation of vibrons as a coherent vibrational mode is described by an analog of the semiclassical laser theory. We study two models: a model of nonequilibrium three-level system with vibronic mode, and a variant of a model of lasing without inversion. We conjecture that the dark states discussed in connection with quantum photosynthesis might be related to the mechanism of vibronic “laser” without inversion, which amplifies the transfer of excitons. We prove that in the presence of a vibronic mode the transfer rate of excitons increases, and compute the dependence of the transfer rate on the parameters of the model.