A ladder model for DNA wires: Signatures of phonon-assisted transport


EC IST-FET 38951 Workshop: DNA-based nanowires | event contribution
Link to conference: http://www.s3.infm.it/WS_DNA/
Oct. 7, 2005 - Oct. 8, 2005 | Modena, Italy

We have formulated a minimal tight-binding model to study charge transport in DNA wires in presence of internal vibrational excitations. We assume that the tunneling charge couples to a single long-wave length boson mode, e. g. a torsional mode. The advantage of the model is that the bosonic degrees of freedom can be eliminated by a canonical transformation; this allows for a non-perturbative treatment of the electron-phonon interaction. We further investigate ordered structures as is the case of Poly(GC) oligomers as well as arbitrary base pair sequences by modifying appropriately the onsite energies. This latter case is of interest to make contact with recent experiments on suspended DNA wires with complex sequence which have shown unexpectedly high currents of the order of 100-200 nA (H. Cohen et al., Proc. Natl. Acad. Sci. 102, 11589 (2005)).


Authors

A ladder model for DNA wires: Signatures of phonon-assisted transport


EC IST-FET 38951 Workshop: DNA-based nanowires | event contribution
Link to conference: http://www.s3.infm.it/WS_DNA/
Oct. 7, 2005 - Oct. 8, 2005 | Modena, Italy

We have formulated a minimal tight-binding model to study charge transport in DNA wires in presence of internal vibrational excitations. We assume that the tunneling charge couples to a single long-wave length boson mode, e. g. a torsional mode. The advantage of the model is that the bosonic degrees of freedom can be eliminated by a canonical transformation; this allows for a non-perturbative treatment of the electron-phonon interaction. We further investigate ordered structures as is the case of Poly(GC) oligomers as well as arbitrary base pair sequences by modifying appropriately the onsite energies. This latter case is of interest to make contact with recent experiments on suspended DNA wires with complex sequence which have shown unexpectedly high currents of the order of 100-200 nA (H. Cohen et al., Proc. Natl. Acad. Sci. 102, 11589 (2005)).


Authors