Vibration-enhanced quantum transport

In this paper, we study the role of collective vibrational motion in the phenomenon of electronic energy transfer (EET) along a chain of coupled electronic dipoles with varying excitation frequencies. Previous experimental work on EET in conjugated polymer samples suggested that the common structural framework of the macromolecule introduces correlations in the energy gap fluctuations that cause coherent EET. Inspired by these results, we present a simple model in which a driven nanomechanical resonator mode modulates the excitation energy of coupled quantum dots and we find that this can indeed lead to an enhancement in the transport of excitations across the quantum network. Disorder in the on-site energies is a key requirement for this to occur. We also show that, in this solid state system, phase information is partially retained in the transfer process, as experimentally demonstrated in conjugated polymer samples. Consequently, this mechanism of vibration-enhanced quantum transport might find applications in quantum information transfer of qubit states or entanglement. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft