S. A. Ketabi and H. F. Khozestani
Iranian J. Physics Research - Vol. 14, No. 3, 67-72, , - October, 2014 - .
Publication year: 2014

Abstract:A numerical study is presented to investigate the electronic transport properties through a synthetic DNA molecule based on a quasiperiodic arrangement of its constituent nucleotides. Using a generalized Green’s function technique, the electronic conduction through the poly(GACT)-poly(CTGA) DNA molecule in a metal/DNA/metal model structure has been studied. Making use of a renormalization scheme we transform the Hamiltonian of double-stranded DNA (dsDNA) molecule to an effective Hamiltonian corresponding to a one-dimensional chain in which the effective on-site energies are arranged as a quasiperiodic lattice according to Fibonacci sequence. The room temperature current-voltage characteristic of dsDNA has been investigated in this Fibonacci model and compared with those corresponding to poly(GACT)-poly(CTGA) DNA molecule. Our results indicate the main effect of the quasiperiodic arrangement of the nucleotides as the Fibonacci sequence on the electronic spectrum structure of the dsDNA is that the energy band gaps of the molecule have a tendency for suppression. The room temperature I-V characteristic of the DNA Fibonacci model shows a linear and ohmic-like behavior.