Dynamics and quantumness of excitation energy transfer through a complex quantum network

TL;DR

This paper investigates how quantum coherence and environmental factors influence excitation energy transfer in a complex quantum network, revealing insights into the robustness and quantum features of EET.

Contribution

It introduces a simple model analyzing the interplay of coherence, noise, and environment in EET, highlighting the role of quantum effects in energy transfer efficiency.

Findings

Quantum coherence enhances EET efficiency.

Environmental noise can maintain robustness of EET.

Quantum features are crucial for understanding energy transfer dynamics.

Abstract

Understanding the mechanisms of efficient and robust energy transfer in organic systems provides us with new insights for the optimal design of artificial systems. In this paper, we explore the dynamics of excitation energy transfer (EET) through a complex quantum network by a toy model consisting of three sites coupled to environments. We study how the coherent evolution and the noise-induced decoherence work together to reach efficient EET and illustrate the role of the phase factor attached to the coupling constant in the EET. By comparing the differences between the Markovian and non-Markovian dynamics, we discuss the effect of environment and the spatial structure of system on the dynamics and the efficiency of EET. A intuitive picture is given to show how the exciton is transferred through the system. Employing the simple model, we show the robustness of EET efficiency under the influence of the environment and elucidate the important role of quantum coherence in EET. We go further to study the quantum feature of the EET dynamics by {\it quantumness} and show the importance of quantum coherence from a new respect. We calculate the energy current in the EET and its quantumness, results for different system parameters are presented and discussed.