Chapter 20
Bath Correlation Effects on Inelastic Charge
Transport Through DNA Junctions
Tal Simon, Daria Brisker-Klaiman, and Uri Peskin
Abstract The effect of correlations in bath-assisted inelastic transport through
DNA molecular junctions is studied. Assigning physical meaning to the correlated bath modes, we examine the relative contributions of different types of nuclear modes to the inelastic transport. In particular, we demonstrate that intra-strand
(backbone modes) and inter-strand (Hydrogen bonds) modes have different contributions to the current, and thus can be associated with a measurable phenomenon.
This work emphasizes the important effect of bath correlations on quantum transport, as pointed out recently also in the context of electron energy transport in biomolecular environment. The approach presented in this work is complementary to
detailed atomistic simulations which account for specific intra-molecular and intermolecular vibrational modes.
20.1 Introduction
The mechanism of charge transport (CT) through DNA has been under intensive
study. Much of the work was devoted to photochemical experiments in which charge
(hole, typically) is transiently injected into one end of the molecule, and the rate
of transport through the molecule is monitored. Most experiments which aim to
identify the CT mechanism in DNA focus on the effects of the number of base
pairs [1–5], or the temperature [6, 7]. Different mechanisms were attributed to the
transport process under different conditions, including tunneling (superexchange),
or hopping (kinetic transport) [8–13] in the off-resonant regime, and ballistic or inelastic transport in resonant tunneling [14, 15]. Only few experiments measured directly the single molecule conductance of DNA [4, 6, 16–18] in a molecular junction
setup [19, 20], where a molecule is placed between two macroscopic leads and the
steady state current is measured. Particularly interesting are experiments in which
the connection strategy between the double helix structure and the two electrodes in
a junction configuration can be controlled [18].
U. Peskin (B)
Schulich Faculty of Chemistry, Technion—Israel Institute of Technology, Haifa 32000, Israel
e-mail: uri@tx.technion.ac.il
M. Hotokka et al. (eds.), Advances in Quantum Methods and Applications in
Chemistry, Physics, and Biology, Progress in Theoretical Chemistry and Physics 27,
DOI 10.1007/978-3-319-01529-3_20,
© Springer International Publishing Switzerland 2013
361
Bath Correlation Effects on Inelastic Charge
Transport Through DNA Junctions
Tal Simon, Daria Brisker-Klaiman, and Uri Peskin
Abstract The effect of correlations in bath-assisted inelastic transport through
DNA molecular junctions is studied. Assigning physical meaning to the correlated bath modes, we examine the relative contributions of different types of nuclear modes to the inelastic transport. In particular, we demonstrate that intra-strand
(backbone modes) and inter-strand (Hydrogen bonds) modes have different contributions to the current, and thus can be associated with a measurable phenomenon.
This work emphasizes the important effect of bath correlations on quantum transport, as pointed out recently also in the context of electron energy transport in biomolecular environment. The approach presented in this work is complementary to
detailed atomistic simulations which account for specific intra-molecular and intermolecular vibrational modes.
20.1 Introduction
The mechanism of charge transport (CT) through DNA has been under intensive
study. Much of the work was devoted to photochemical experiments in which charge
(hole, typically) is transiently injected into one end of the molecule, and the rate
of transport through the molecule is monitored. Most experiments which aim to
identify the CT mechanism in DNA focus on the effects of the number of base
pairs [1–5], or the temperature [6, 7]. Different mechanisms were attributed to the
transport process under different conditions, including tunneling (superexchange),
or hopping (kinetic transport) [8–13] in the off-resonant regime, and ballistic or inelastic transport in resonant tunneling [14, 15]. Only few experiments measured directly the single molecule conductance of DNA [4, 6, 16–18] in a molecular junction
setup [19, 20], where a molecule is placed between two macroscopic leads and the
steady state current is measured. Particularly interesting are experiments in which
the connection strategy between the double helix structure and the two electrodes in
a junction configuration can be controlled [18].
U. Peskin (B)
Schulich Faculty of Chemistry, Technion—Israel Institute of Technology, Haifa 32000, Israel
e-mail: uri@tx.technion.ac.il
M. Hotokka et al. (eds.), Advances in Quantum Methods and Applications in
Chemistry, Physics, and Biology, Progress in Theoretical Chemistry and Physics 27,
DOI 10.1007/978-3-319-01529-3_20,
© Springer International Publishing Switzerland 2013
361