Charge migration mechanisms in the DNA at finite temperature revisited; from quasi-ballistic to subdiffusive transport

Abstract

Various charge migration mechanisms in the DNA are studied within the framework of the Peyrard-Bishop-Holstein model which has been widely used to address charge dynamics in this macromolecule. To analyze these mechanisms we consider characteristic size and time scales of the fluctuations of the electronic and vibrational subsystems. It is shown, in particular, that due to substantial differences in these timescales polaron formation is unlikely within a broad range of temperatures. We demonstrate that at low temperatures electronic transport can be quasi-ballistic. For high temperatures, we propose an alternative to polaronic charge migration mechanism: the fluctuation-assisted one, in which the electron dynamics is governed by relatively slow fluctuations of the vibrational subsystem. We argue also that the discussed methods and mechanisms can be relevant for other organic macromolecular systems, such as conjugated polymers and molecular aggregates.

References in corpus (6)

• DNA double helices for single molecule electronics
• Nonequilibrium dynamics of the Holstein polaron driven by external electric field
• Electronic structure and carrier transfer in B-DNA monomer polymers and dimer polymers: Stationary and time-dependent aspects of wire model vs. extended ladder model
• Robust signatures in the current-voltage characteristics of DNA molecules oriented between two graphene nanoribbon electrodes
• Probing quantum-mechanical level repulsion in disordered systems by means of time-resolved selectively-excited resonance fluorescence
• Environment effects on the electric conductivity of the DNA