Gate Control of the Conduction Mechanism Transition from Tunneling to Thermally Activated Hopping

We explore gate control of electron transport through molecules with different repeat units. In the framework of reduced density matrix theory, the computational results show (i) exponential decay in the tunneling regime and (ii) Arrhenius behavior and similar activation energies in the hopping regime, which are qualitatively consistent with experimental observations. Moreover, the gate enables tuning of the activation energy, indicating that the continuous transition from tunneling to hopping could be experimentally observed. The activation energy-gate voltage characteristics are introduced to investigate different conduction regimes.