Nearest-neighbor inter-strand coupling effects on electron transport through DNA molecules

In this research, an updated tight binding model including nearest-neighbor inter-strand hopping (NIH) strengths for quantum mechanical electron transport through double-stranded DNA molecules is proposed. The motivation for including these additional couplings is their similar hopping mechanism for electron tunneling in computations of DNA electron transport. Results are examined for a 30 base-pair, poly(G)--poly(C) DNA molecule which demonstrates the effects of NIH strengths on energy transmission and current-voltage (I-V) characteristics. It is found that enhancement of transmission spectra is observed with these couplings, and subsequent novel features are revealed on the I-V characteristics under various electrode-molecule contact conditions.