Energy transfer, correlations and decoherence in a dimer in terms of the two-level atomic distances

In this manuscript, we study the coherent single-excitation energy transfer for a dimer system consisting of a donor and an acceptor modeled by two-level systems (TLSs), which are immersed in common thermal environment. We illustrate the effects of the distance between TLSs and temperature of the thermal reservoir on the energy transfer process considering collective damping and dipole–dipole interaction. Concretely, the control and enhancement of the probability during the time evolution is performed by a suitable choice of the distance between TLSs with respect to the temperature of the reservoir. On the other hand, we study the time evolution of the quantum and classical correlations of the TLSs-state through calculating concurrence and quantum discord. We find that the dynamical behavior of quantum and classical correlations dynamics in thermal reservoir is similar to vacuum reservoir with slight decrease in the amount of correlations. These correlations are also very sensitive to the TLSs-distance and when the distance becomes significantly large, the amount of correlations exponentially decrease with the time. Finally, we explore the relationship between the probability and correlations during the evolution and shows that quantum and classical correlations can be created during the process of excitation energy transfer.