title: Effect of mechanical stretching on DNA conductance.
abstract: Studying the structural and charge transport properties in DNA is important for unraveling molecular scale processes and developing device applications of DNA molecules. Here we study the effect of mechanical stretching-induced structural changes on charge transport in single DNA molecules. The charge transport follows the hopping mechanism for DNA molecules with lengths varying from 6 to 26 base pairs, but the conductance is highly sensitive to mechanical stretching, showing an abrupt decrease at surprisingly short stretching distances and weak dependence on DNA length. We attribute this force-induced conductance decrease to the breaking of hydrogen bonds in the base pairs at the end of the sequence and describe the data with a mechanical model.
authors.affiliation: Center for Bioelectronics and Biosensors, Biodesign Institute, School of Electrical, Energy and Computer Engineering, Arizona State University , Tempe, Arizona 85287-5801, United States.
authors.forename: Christopher
authors.initials: C
authors.lastname: Bruot
authors.forename: Limin
authors.initials: L
authors.lastname: Xiang
authors.forename: Julio L
authors.initials: JL
authors.lastname: Palma
authors.forename: Nongjian
authors.initials: N
authors.lastname: Tao
mesh_terms: D004247:DNA / Q000737:chemistry; D004553:Electric Conductivity; D004579:Electron Transport; D006860:Hydrogen Bonding; D055595:Mechanical Phenomena; D008958:Models, Molecular; D009690:Nucleic Acid Conformation
chemical_list: D004247:DNA
keywords: DNA conductance; STM; break junction; mechanical properties; molecular electronics; single molecule