Enhancement of transport in DNA-like systems induced by backbone disorder.
We report a theoretical study highlighting the fundamental effects of backbone disorder which simulates the environmental complications on charge transport properties of biological and synthetic DNA molecules. Based on effective tight-binding models of duplex DNA, the Lyapunov coefficient and current-voltage characteristics are numerically calculated by varying the backbone disorder degree. In contrast to the localization picture that the conduction of duplex DNA becomes poorer when the backbone disorder degree is increased, we find that the backbone disorder can enhance the charge transport ability of the DNA molecules when the environment-induced disorder surpasses a critical value, giving rise to a semiconducting-metallic transition. The physical origin for this is traced back to the antiresonant effects. These results provide a scenario to interpret a variety of transport behaviors observed in DNA molecules and suggest perspectives for future experiments intending to control the charge transport through DNA-based nanodevices.
Guo
Ai-Min
AM
National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China.
Xiong
Shi-Jie
SJ
Yang
Zhi
Z
Zhu
Hong-Jun
HJ
D010582:Bacteriophage lambda; D001693:Biological Transport, Active; D055592:Biophysical Phenomena; D002892:Chromosomes, Human, Pair 22 / Q000737:chemistry / Q000378:metabolism; D004247:DNA / Q000737:chemistry* / Q000378:metabolism*; D004279:DNA, Viral / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008954:Models, Biological; D015394:Molecular Structure; D049329:Nanostructures; D011061:Poly A / Q000737:chemistry; D011066:Poly C / Q000737:chemistry; D011068:Poly G / Q000737:chemistry; D011071:Poly T / Q000737:chemistry; D055672:Static Electricity; D013816:Thermodynamics
D004279:DNA, Viral; D011061:Poly A; D011071:Poly T; D011068:Poly G; C008961:poly G-poly C; C008950:poly A-T; D011066:Poly C; D004247:DNA